Don't define wxWidgetImpl::SetLabelMarkup() when wxUSE_MARKUP is off and
definitely don't reimplement it in wxButtonCocoaImpl as this code doesn't
compile without markup support.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67103 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775