When item release is called, the parent is already null.  We need the
parent to pass to nvmet_referral_disable so hook it up to
->disconnect_notify.
Reported-by: NTony Asleson <tasleson@redhat.com>
Signed-off-by: NSagi Grimberg <sagi@grimberg.me>
Reviewed-by: NChaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>