State recovery currently relies on being able to find a valid
nfs_open_context in the inode->open_files list.
We therefore need to put the nfs_open_context on the list while
we're still protected by the sp->so_reclaim_seqcount in order
to avoid reboot races.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>