Replace X-allocation functions with their C89 counterparts

The only remaining X-functions used in server are XNF*, the rest is converted to
plain alloc/calloc/realloc/free/strdup.

X* functions are still exported from server and x* macros are still defined in
header file, so both ABI and API are not affected by this change.

Signed-off-by: Mikhail Gusarov <dottedmag@dottedmag.net>
Reviewed-by: Peter Hutterer <peter.hutterer@who-t.net>

render/mipict.c

@@ -106,7 +106,7 @@ miChangePictureClip (PicturePtr    pPicture,
 	if (!clientClip)
 	    return BadAlloc;
 	clientClipType = CT_REGION;
-	xfree(value);
+	free(value);
 	break;
     }
     (*ps->DestroyPictureClip) (pPicture);