QtSupport: Expand path variables only to local paths

It's what it used to do and actually better for the docker case where
the two only active use of these in form of %{Qt:QT_INSTALL_PREFIX}
are in a cmake build context that would require (device-)local path.

Long term we might want to use a variation of registerFileVariable
here without changing semantics on the user side.

Change-Id: If8dd77ac0b94ede41dbfe322802d5ef6c0b043ee
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/plugins/qtsupport/baseqtversion.cpp

@@ -1486,67 +1486,67 @@ BaseQtVersion::createMacroExpander(const std::function<const BaseQtVersion *()>
                                QtKitAspect::tr(
                                    "The installation prefix of the current Qt version."),
                                versionProperty([](const BaseQtVersion *version) {
-                                   return version->prefix().toString();
+                                   return version->prefix().path();
                                }));
 
     expander->registerVariable("Qt:QT_INSTALL_DATA",
                                QtKitAspect::tr(
                                    "The installation location of the current Qt version's data."),
                                versionProperty([](const BaseQtVersion *version) {
-                                   return version->dataPath().toString();
+                                   return version->dataPath().path();
                                }));
 
     expander->registerVariable("Qt:QT_HOST_PREFIX",
                                QtKitAspect::tr(
                                    "The host location of the current Qt version."),
                                versionProperty([](const BaseQtVersion *version) {
-                                   return version->hostPrefixPath().toString();
+                                   return version->hostPrefixPath().path();
                                }));
 
     expander->registerVariable("Qt:QT_HOST_LIBEXECS",
                                QtKitAspect::tr("The installation location of the current Qt "
                                                "version's internal host executable files."),
                                versionProperty([](const BaseQtVersion *version) {
-                                   return version->hostLibexecPath().toString();
+                                   return version->hostLibexecPath().path();
                                }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_HEADERS",
         QtKitAspect::tr("The installation location of the current Qt version's header files."),
         versionProperty(
-            [](const BaseQtVersion *version) { return version->headerPath().toString(); }));
+            [](const BaseQtVersion *version) { return version->headerPath().path(); }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_LIBS",
         QtKitAspect::tr("The installation location of the current Qt version's library files."),
         versionProperty(
-            [](const BaseQtVersion *version) { return version->libraryPath().toString(); }));
+            [](const BaseQtVersion *version) { return version->libraryPath().path(); }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_DOCS",
         QtKitAspect::tr(
             "The installation location of the current Qt version's documentation files."),
         versionProperty(
-            [](const BaseQtVersion *version) { return version->docsPath().toString(); }));
+            [](const BaseQtVersion *version) { return version->docsPath().path(); }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_BINS",
         QtKitAspect::tr("The installation location of the current Qt version's executable files."),
-        versionProperty([](const BaseQtVersion *version) { return version->binPath().toString(); }));
+        versionProperty([](const BaseQtVersion *version) { return version->binPath().path(); }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_LIBEXECS",
         QtKitAspect::tr(
             "The installation location of the current Qt version's internal executable files."),
         versionProperty(
-            [](const BaseQtVersion *version) { return version->libExecPath().toString(); }));
+            [](const BaseQtVersion *version) { return version->libExecPath().path(); }));
 
     expander
         ->registerVariable("Qt:QT_INSTALL_PLUGINS",
                            QtKitAspect::tr(
                                "The installation location of the current Qt version's plugins."),
                            versionProperty([](const BaseQtVersion *version) {
-                               return version->pluginPath().toString();
+                               return version->pluginPath().path();
                            }));
 
     expander
@@ -1554,7 +1554,7 @@ BaseQtVersion::createMacroExpander(const std::function<const BaseQtVersion *()>
                            QtKitAspect::tr(
                                "The installation location of the current Qt version's QML files."),
                            versionProperty([](const BaseQtVersion *version) {
-                               return version->qmlPath().toString();
+                               return version->qmlPath().path();
                            }));
 
     expander
@@ -1562,34 +1562,34 @@ BaseQtVersion::createMacroExpander(const std::function<const BaseQtVersion *()>
                            QtKitAspect::tr(
                                "The installation location of the current Qt version's imports."),
                            versionProperty([](const BaseQtVersion *version) {
-                               return version->importsPath().toString();
+                               return version->importsPath().path();
                            }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_TRANSLATIONS",
         QtKitAspect::tr("The installation location of the current Qt version's translation files."),
         versionProperty(
-            [](const BaseQtVersion *version) { return version->translationsPath().toString(); }));
+            [](const BaseQtVersion *version) { return version->translationsPath().path(); }));
 
     expander->registerVariable(
         "Qt:QT_INSTALL_CONFIGURATION",
         QtKitAspect::tr("The installation location of the current Qt version's translation files."),
         versionProperty(
-            [](const BaseQtVersion *version) { return version->configurationPath().toString(); }));
+            [](const BaseQtVersion *version) { return version->configurationPath().path(); }));
 
     expander
         ->registerVariable("Qt:QT_INSTALL_EXAMPLES",
                            QtKitAspect::tr(
                                "The installation location of the current Qt version's examples."),
                            versionProperty([](const BaseQtVersion *version) {
-                               return version->examplesPath().toString();
+                               return version->examplesPath().path();
                            }));
 
     expander->registerVariable("Qt:QT_INSTALL_DEMOS",
                                QtKitAspect::tr(
                                    "The installation location of the current Qt version's demos."),
                                versionProperty([](const BaseQtVersion *version) {
-                                   return version->demosPath().toString();
+                                   return version->demosPath().path();
                                }));
 
     expander->registerVariable("Qt:QMAKE_MKSPECS",