nvme-tcp: fix error codes in nvme_tcp_setup_ctrl()

These error paths currently return success but they should return
-EOPNOTSUPP.

Fixes: 73ffcefc ("nvme-tcp: check sgl supported by target")
Fixes: 3f2304f8 ("nvme-tcp: add NVMe over TCP host driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>