mds: remove wrong assertion for remote frozen authpin

For across authority rename, the MDS first freezes the source inode's
authpin. It happens while the source dentry isn't locked. So when the
inode's authpin become frozen, the source dentry may have changed and
be linked to a different inode.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
mds: include truncate_seq/truncate_size in filelock's state

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Merge pull request #1639 from ceph/wip-multimds

Wip multimds

Reviewed-by: Sage Weil <sage@inktank.com>