qla2xxx: Cleanup TMF code translation from qla_target

Move code code which converts Task Mgmt Command flags for
ATIO to TCM #defines, from qla2xxx driver to tcm_qla2xxx
driver.

Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>