make more Init() functions private

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@72604 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/mdi.h

@@ -67,11 +67,11 @@ public:
     virtual void OnInternalIdle();
 
 protected:
-    void Init();
     virtual void DoGetClientSize(int* width, int* height) const;
 
 private:
     friend class wxMDIChildFrame;
+    void Init();
 
     DECLARE_DYNAMIC_CLASS(wxMDIParentFrame)
 };