macros: Add fallback defines for non-GCC compilers

I forgot to add the fallback definitions in case we're not using GCC;
without them, anybody using non-GCC compilers will get a build error.

https://bugzilla.gnome.org/show_bug.cgi?id=752272

clutter/clutter-macros.h

@@ -100,6 +100,9 @@
 #define _CLUTTER_GNUC_DO_PRAGMA(x) _Pragma(G_STRINGIFY (x))
 #define _CLUTTER_DEPRECATED_MACRO _CLUTTER_GNUC_DO_PRAGMA(GCC warning "Deprecated macro")
 #define _CLUTTER_DEPRECATED_MACRO_FOR(f) _CLUTTER_GNUC_DO_PRAGMA(GCC warning #f)
+#else
+#define _CLUTTER_DEPRECATED_MACRO
+#define _CLUTTER_DEPRECATED_MACRO_FOR(f)
 #endif
 
 /* these macros are used to mark deprecated functions, and thus have to be