CMakeProjectManager: Add "install/strip" and "package" special targets

The Ninja / Makefile generator supports these targets as seen at:

https://cmake.org/cmake/help/latest/generator/Ninja.html
https://cmake.org/cmake/help/latest/generator/Unix%20Makefiles.html

Fixes: QTCREATORBUG-22620
Fixes: QTCREATORBUG-22047
Change-Id: Id0105ae59b7d699f0da637efed4efa337769b601
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/cmakeprojectmanager/cmakebuildstep.cpp

@@ -416,6 +416,16 @@ QString CMakeBuildStep::installTarget()
     return QString("install");
 }
 
+QString CMakeBuildStep::installStripTarget()
+{
+    return QString("install/strip");
+}
+
+QString CMakeBuildStep::packageTarget()
+{
+    return QString("package");
+}
+
 QString CMakeBuildStep::testTarget()
 {
     return QString("test");
@@ -423,7 +433,8 @@ QString CMakeBuildStep::testTarget()
 
 QStringList CMakeBuildStep::specialTargets()
 {
-    return { allTarget(), cleanTarget(), installTarget(), testTarget() };
+    return { allTarget(), cleanTarget(), installTarget(), installStripTarget(),
+             packageTarget(), testTarget() };
 }
 
 QString CMakeBuildStep::activeRunConfigTarget() const

src/plugins/cmakeprojectmanager/cmakebuildstep.h

@@ -72,6 +72,8 @@ public:
     static QString cleanTarget();
     static QString allTarget();
     static QString installTarget();
+    static QString installStripTarget();
+    static QString packageTarget();
     static QString testTarget();
     static QStringList specialTargets();