dm mpath: eliminate need to use scsi_device_from_queue

Instead of scsi_device_from_queue(), use scsi_dh_attached_handler_name()
-- whose implementation uses scsi_device_from_queue() to avoid trying to
access SCSI-specific resources from non-SCSI devices.

Fixes buildbot reported issue when CONFIG_SCSI isn't set:
 ERROR: "scsi_device_from_queue" [drivers/md/dm-multipath.ko] undefined!

Fixes: 8d47e659

 ("dm mpath: remove unnecessary NVMe branching in favor of scsi_dh checks")
Signed-off-by: Mike Snitzer <snitzer@redhat.com>