Remove redundant 'if defined' check

WindowMaker.h already #includes wconfig.h, which checks exactly
the same thing. So remove it from WindowMaker.h.

However, it would be better if WindowMaker.h didn't include
wconfig.h at all. The only reason I see for the inclusion is
the check for KEEP_XKB_LOCK_STATUS, defined in wconfig.h.
But that can be probably cleaned up too (I guess modern X's
enable XKB stuff that by default, by I haven't checked)

But anyway.

src/WindowMaker.h

@@ -23,21 +23,10 @@
 #define WINDOWMAKER_H_
 
 #include "wconfig.h"
-
 #include <assert.h>
 #include <limits.h>
-
 #include <WINGs/WINGs.h>
 
-#if defined(HAVE_LIBINTL_H) && defined(I18N)
-# include <libintl.h>
-# define _(text) gettext(text)
-#else
-# define _(text) (text)
-#endif
-
-
-
 
 /* class codes */
 typedef enum {