fsnotify: make dnotify_fsnotify_ops const

Make this const as it is never modified.
Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/notify/dnotify/dnotify.c

@@ -133,7 +133,7 @@ static void dnotify_free_mark(struct fsnotify_mark *fsn_mark)
 	kmem_cache_free(dnotify_mark_cache, dn_mark);
 }
 
-static struct fsnotify_ops dnotify_fsnotify_ops = {
+static const struct fsnotify_ops dnotify_fsnotify_ops = {
 	.handle_event = dnotify_handle_event,
 	.free_mark = dnotify_free_mark,
 };