scsi: qla2xxx: Fix I/O failures during remote port toggle testing

Driver was using a lower value for dev_loss_tmo making it more prone to I/O
failures during remote port toggle testing. Set dev_loss_tmo to zero during
remote port registration to allow nvme-fc default dev_loss_tmo to be used,
which is higher than what driver was using.

Link: https://lore.kernel.org/r/20200904045128.23631-2-njavali@marvell.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Himanshu Madhani <hmadhani@marvell.com>
Signed-off-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>