scsi: qla2xxx: Defer chip reset until target mode is enabled

[ Upstream commit 93eca6135183f7a71e36acd47655a085ed11bcdc ]

For target mode, any chip reset triggered before target mode is enabled will
be held off until user is ready to enable.  This prevents the chip from
starting or running before it is intended.

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: Sasha Levin <sashal@kernel.org>