Removed WXWIN_COMPATIBILITY_2_2 together with code guarded by it.

Changed default for WXWIN_COMPATIBILITY_2_4 to 0.
  Added WXWIN_COMPATIBILITY_2_6 (defaults to 1).
  Ran build/update-setup-h.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@35858 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/generic/treectlg.cpp

@@ -3635,13 +3635,4 @@ void wxGenericTreeCtrl::SetItemSelectedImage(const wxTreeItemId& item, int image
 
 #endif // WXWIN_COMPATIBILITY_2_4
 
-#if WXWIN_COMPATIBILITY_2_2
-
-wxTreeItemId wxGenericTreeCtrl::GetParent(const wxTreeItemId& item) const
-{
-    return GetItemParent( item );
-}
-
-#endif  // WXWIN_COMPATIBILITY_2_2
-
 #endif // wxUSE_TREECTRL