Replace wxST_MARKUP style with wxControl::SetLabelMarkup().

This is an incompatible change which removes the wxStaticText-specific
wxST_MARKUP style and adds wxControl::SetLabelMarkup() replacing it.

It doesn't actually change anything yet but it simplifies wxStaticText code a
lot by getting rid of many markup-related functions in it which had to behave
differently depending on whether wxST_MARKUP was used or not and also paves
way for adding markup support for the other controls in the future.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67055 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/osx/stattext_osx.cpp

@@ -62,11 +62,11 @@ void wxStaticText::SetLabel(const wxString& label)
     )
     {
         // leave ellipsization to the OS
-        DoSetLabel(GetLabelWithoutMarkup());
+        DoSetLabel(GetLabel());
     }
     else // not supported natively
     {
-        DoSetLabel(GetEllipsizedLabelWithoutMarkup());
+        DoSetLabel(GetEllipsizedLabel());
     }
 
     if ( !(GetWindowStyle() & wxST_NO_AUTORESIZE) &&