ceph: record 'offset' for each entry of readdir result

This is preparation for using hash value as dentry 'offset'

Signed-off-by: Yan, Zheng <zyan@redhat.com>
diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h
index 2a86581..4ce19d8 100644
--- a/fs/ceph/mds_client.h
+++ b/fs/ceph/mds_client.h
@@ -52,6 +52,7 @@
 	u32                           name_len;
 	struct ceph_mds_reply_lease   *lease;
 	struct ceph_mds_reply_info_in inode;
+	loff_t			      offset;
 };
 
 /*