NFSv4 reduce attribute requests for open reclaim

We currently make no distinction in attribute requests between normal OPENs
and OPEN with CLAIM_PREVIOUS.  This offers more possibility of failures in
the GETATTR response which foils OPEN reclaim attempts.

Reduce the requested attributes to the bare minimum needed to update the
reclaim open stateid and split nfs4_opendata_to_nfs4_state processing
accordingly.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>