scsi: qla2xxx: Combine Active command arrays.

Merge active/outstanding cmd arrays from target side and initiator side
together in prepration for Target Multi Queue support.

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>