QuickDesigner: Fix last (?) occurence of 4.6 as version of Qt namespace

Reviewed-by: Thomas Hartmann

src/plugins/qmldesigner/designercore/include/model.h

@@ -78,7 +78,7 @@ public:
 
     virtual ~Model();
 
-    static Model *create(QString type, int major = 4, int minor = 6);
+    static Model *create(QString type, int major = 4, int minor = 7);
 
     Model *masterModel() const;
     void setMasterModel(Model *model);