CppTools: De-duplicate code for CppProjectUpdater

Centralize gathering the kit, toolchains and qt version.

Change-Id: I6bd586ac7925e2ee556fd119f1dab096cd500e41
Reviewed-by: Christian Kandeler <christian.kandeler@qt.io>

src/plugins/cpptools/cpptools.pro

@@ -102,7 +102,8 @@ HEADERS += \
     cpptools_clangtidychecks.h \
     cppmodelmanagerinterface.h \
     cppbuiltinmodelmanagersupport.h \
-    headerpathfilter.h
+    headerpathfilter.h \
+    cppkitinfo.h
 
 SOURCES += \
     abstracteditorsupport.cpp \
@@ -189,7 +190,8 @@ SOURCES += \
     cppprojectpartchooser.cpp \
     wrappablelineedit.cpp \
     cppbuiltinmodelmanagersupport.cpp \
-    headerpathfilter.cpp
+    headerpathfilter.cpp \
+    cppkitinfo.cpp
 
 FORMS += \
     clangdiagnosticconfigswidget.ui \