Include <config.h> uniformly in oldXMenu sources.

Include <config.h> uniformly in oldXMenu sources.

* Activate.c, AddPane.c, AddSel.c, ChgPane.c, ChgSel.c, Create.c:
* InsPane.c, InsSel.c, Internal.c, XMakeAssoc.c:
Do not include <config.h>, since XMenuInt.h does that now.
* XLookAssoc.c, XMenuInt.h: Include <config.h>.
This avoids a build failure when configuring on Fedora 17
--with-x-toolkit=no, reported by Dmitry Andropov in
<http://lists.gnu.org/archive/html/emacs-devel/2012-12/msg00078.html>.