commit 46243860 upstream.

While looking at hch's recent conversion to drop the MSG_*_TAG
definitions, I noticed a long standing bug in vhost-scsi where
the VIRTIO_SCSI_S_* attribute definitions where incorrectly
being passed directly into target_submit_cmd_map_sgls().

This patch adds the missing virtio-scsi to TCM/SAM task attribute
conversion.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
[ luis: backported to 3.16:
  - replaced TCM_*_TAG by MSG_*_TAG ]
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>