NFSD: Do not allow NFSv4 (N)VERIFY to check POSIX ACL attributes

NFSD: Do not allow NFSv4 (N)VERIFY to check POSIX ACL attributes

Section 9.3 of draft-ietf-nfsv4-posix-acls-00 prohibits use of
the POSIX ACL attributes with VERIFY and NVERIFY operations: the
server MUST reply NFS4ERR_INVAL when a client attempts this.

Beyond the protocol requirement, comparison of POSIX draft ACLs
via (N)VERIFY presents an implementation challenge. Clients are
not required to order the ACEs within a POSIX ACL in any
particular way, making reliable attribute comparison impractical.

Return nfserr_inval when the client requests FATTR4_POSIX_ACCESS_ACL
or FATTR4_POSIX_DEFAULT_ACL in a VERIFY or NVERIFY operation.

Signed-off-by: Rick Macklem <rmacklem@uoguelph.ca>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>