Utils: Collapse most of porting,h

Taking the Qt 6 branches, leaving some dummies until downstream
adapted.

Change-Id: Ib9b86568d73c341c8f740ba497c3cbfab830d8a1
Reviewed-by: Eike Ziller <eike.ziller@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

src/plugins/classview/classviewsymbolinformation.h

@@ -59,7 +59,7 @@ public:
 
 private:
     const int m_iconType;
-    const Utils::QHashValueType m_hash; // precalculated hash value - to speed up qHash
+    const size_t m_hash; // precalculated hash value - to speed up qHash
     const QString m_name;               // symbol name (e.g. SymbolInformation)
     const QString m_type;               // symbol type (e.g. (int char))
 };