XACE: Adjust the location of the COMPOSITE creation hook.

Avoids incrementing the refcnt if the hook fails.

composite/compext.c

@@ -289,14 +289,14 @@ ProcCompositeNameWindowPixmap (ClientPtr client)
     if (!pPixmap)
 	return BadMatch;
 
-    ++pPixmap->refcnt;
-    
     /* security creation/labeling check */
     rc = XaceHook(XACE_RESOURCE_ACCESS, client, stuff->pixmap, RT_PIXMAP,
 		  pPixmap, RT_WINDOW, pWin, DixCreateAccess);
     if (rc != Success)
 	return rc;
 
+    ++pPixmap->refcnt;
+
     if (!AddResource (stuff->pixmap, RT_PIXMAP, (pointer) pPixmap))
 	return BadAlloc;