nfscl: Use delegation ACE when mounted with nocto

For NFSv4.1/4.2, there is an ACE in the delegation reply.
Without this patch, this ACE is ignored by the NFSv4 client.

This patch enables use of the ACE to avoid the need for
Access RPCs when the "nocto" option is specified.
This requires a NFSv4.1/4.2 server that does not reply
with a bogus ACE that is too generous w.r.t. access permissions.
Note that the recent commit 0d51adee3072 added use of the NFSv4
ACL for generation of the ACE in the reply. This patch might be
needed for this client change to work correctly if NFSv4 ACLs are
being used on the NFSv4.1/4.2 exported file systems.

This only affects NFSv4 mounts with the "nocto" mount option
and only if NFSv4 servers are issuing delegations with ACEs
that specify access. Some NFSv4 servers, such as the Linux
knfsd reply with ACEs that do not allow any access, so this
patch has no effect for them.