(Fx_create_frame): Do xlwmenu hack only if USE_LUCID.

src/xfns.c

@@ -89,8 +89,10 @@ extern void _XEditResCheckMessages ();
    Library.  */
 extern LWLIB_ID widget_id_tick;
 
+#ifdef USE_LUCID
 /* This is part of a kludge--see lwlib/xlwmenu.c.  */
 extern XFontStruct *xlwmenu_default_font;
+#endif
 
 extern void free_frame_menubar ();
 #endif /* USE_X_TOOLKIT */
@@ -3147,7 +3149,7 @@ This function is an internal primitive--use `make-frame' instead.")
 			 "font", "Font", string);
   }
 
-#ifdef USE_X_TOOLKIT
+#ifdef USE_LUCID
   /* Prevent lwlib/xlwmenu.c from crashing because of a bug
      whereby it fails to get any font.  */
   xlwmenu_default_font = f->output_data.x->font;