When building wxGTK under Windows, some MSW-specific options can be defined
but can't be implemented when using GTK, forcefully disable them.
Also a few others that could be implemented but that don't work currently.
Finally, forcefully enable Cairo support as wxGTK always needs it.
Closes#14412.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@71796 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775