qbs build: Do not use relative paths in Export items

Those will be interpreted relative to the importing product in the
future.

Change-Id: I57f6159053acf1e0334d3289de1f93545e2e871b
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

qbs/imports/QtcPlugin.qbs

@@ -46,6 +46,6 @@ QtcProduct {
     Export {
         Depends { name: "cpp" }
         Depends { name: "ExtensionSystem" }
-        cpp.includePaths: ".."
+        cpp.includePaths: exportingProduct.sourceDirectory + "/.."
     }
 }

src/libs/3rdparty/libvterm/vterm.qbs

@@ -30,6 +30,6 @@ QtcLibrary {
 
     Export {
         Depends { name: "cpp" }
-        cpp.includePaths: "include"
+        cpp.includePaths: exportingProduct.sourceDirectory + "/include"
     }
 }

src/libs/modelinglib/modelinglib.qbs

@@ -396,8 +396,8 @@ QtcLibrary {
 
     Export {
         cpp.includePaths: [
-            ".",
-            "./qtserialization/inc"
+            exportingProduct.sourceDirectory,
+            exportingProduct.sourceDirectory + "/qtserialization/inc"
         ]
     }
 }

src/libs/solutions/spinner/spinner.qbs

@@ -14,7 +14,7 @@ QtcLibrary {
 
     Export {
         Depends { name: "cpp" }
-        cpp.includePaths: ".."
+        cpp.includePaths: exportingProduct.sourceDirectory + "/.."
     }
 }
 

src/libs/solutions/tasking/tasking.qbs

@@ -22,7 +22,10 @@ QtcLibrary {
 
     Export {
         Depends { name: "cpp" }
-        cpp.includePaths: ["..", "../.."]
+        cpp.includePaths: [
+            exportingProduct.sourceDirectory + "/..",
+            exportingProduct.sourceDirectory + "/../.."
+        ]
     }
 }
 

src/libs/utils/utils.qbs

@@ -475,6 +475,6 @@ QtcLibrary {
     Export {
         Depends { name: "Qt"; submodules: ["concurrent", "widgets" ] }
         Depends { name: "Tasking" }
-        cpp.includePaths: "mimetypes2"
+        cpp.includePaths: exportingProduct.sourceDirectory + "/mimetypes2"
     }
 }