Properly fix CLOSE4

It turns out Ganesha really wasn't handling a CLOSE with an invalid
stateid properly. If we detect that the stateid belongs to a valid
clientid, we can return NFS4_OK, but in that case, we must also
update the lease.

We also need to make sure that ONLY CLOSE is affected by this
functionality. V4.1 also handles leases differently.

Signed-off-by: Frank S. Filz <ffilz@us.ibm.com>