scsi: qla2xxx: Prevent PRLI in target mode

scsi: qla2xxx: Prevent PRLI in target mode

[ Upstream commit fcb16d9a8ecf1e9bfced0fc654ea4e2caa7517f4 ]

In a case when the initiator in P2P mode by some circumstances does not
send PRLI, the target, in a case when the target port's WWPN is less than
initiator's, changes the discovery state in DSC_GNL. When gnl completes it
sends PRLI to the initiator.

Usually the initiator in P2P mode always sends PRLI. We caught this issue
on Linux stable v5.4.6 https://www.spinics.net/lists/stable/msg458515.html.

Fix this particular corner case in the behaviour of the P2P mod target
login state machine.

Link: https://lore.kernel.org/r/20210422153414.4022-1-a.kovaleva@yadro.com
Fixes: a9ed06d4e640 ("scsi: qla2xxx: Allow PLOGI in target mode")
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>