tcm_loop: Enable DIF/DIX modes in SCSI host LLD

tcm_loop: Enable DIF/DIX modes in SCSI host LLD

This patch updates tcm_loop_driver_probe() to set protection
information using scsi_host_set_prot() and scsi_host_set_guard(),
which currently enabled all modes of DIF/DIX protection, minus
DIX TYPE0.

Also, update tcm_loop_submission_work() to pass struct scsi_cmnd
related protection into target_submit_cmd_map_sgls() during CDB
dispatch.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>