linux-imx

NFSv4: Don't test open_stateid unless it is set

We need to test the NFS_OPEN_STATE flag for whether or not the
open_stateid is valid.

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Tested-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>