commit 01913b49 upstream.

If decode_getfh failed, nfs4_xdr_dec_open would return 0 since the last
decode_* call must have succeeded.
Signed-off-by: Weston Andros Adamson <dros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>