Make wxEntry(HINSTANCE, ...) available in wxGTK under Windows too.
Refactor the headers to allow this and extract Windows-specific wxEntry()
declarations in wx/msw/init.h from wx/msw/app.h for consistency with the
normal wxEntry(int, char**) declared in wx/init.h.
Closes#14423.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@71890 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
