scsi: qla2xxx: Reduce holding sess_lock to prevent CPU lock-up

commit 0aca77843e2803bf4fab1598b7891c56c16be979 upstream.

- Reduce sess_lock holding to prevent CPU Lock up. sess_lock was held across
  fc_port registration and deletion.  These calls can be blocked by upper
  layer. Sess_lock is also being accessed by interrupt thread.

- Reduce number of loops in processing work_list to prevent kernel complaint
  of CPU lockup or holding sess_lock.

Reported-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Tested-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Fixes: 9ba1cb25c151 ("scsi: qla2xxx: Remove all rports if fabric scan retry fails")
Link: https://lore.kernel.org/linux-scsi/D01377DD-2E86-427B-BA0C-8D7649E37870@oracle.com/T/#t


Signed-off-by: Quinn Tran <quinn.tran@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>