ceph: make sure syncfs flushes all cap snaps

Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index d474141..bf24d88 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -290,6 +290,7 @@
 	 * references (implying they contain no inodes with caps) that
 	 * should be destroyed.
 	 */
+	u64			last_snap_seq;
 	struct rw_semaphore     snap_rwsem;
 	struct rb_root          snap_realms;
 	struct list_head        snap_empty;