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/libs/qmljs/qmljsinterpreter.cpp

@@ -175,7 +175,7 @@ bool FakeMetaObjectWithOrigin::operator ==(const FakeMetaObjectWithOrigin &o) co
     return fakeMetaObject == o.fakeMetaObject;
 }
 
-Utils::QHashValueType qHash(const FakeMetaObjectWithOrigin &fmoo)
+size_t qHash(const FakeMetaObjectWithOrigin &fmoo)
 {
     return qHash(fmoo.fakeMetaObject);
 }