scsi: qla2xxx: Add FC-NVMe command handling

This patch adds logic to handle the completion of FC-NVMe commands and
creates a sub-command in the SRB command structure to manage NVMe
commands.

Signed-off-by: Darren Trapp <darren.trapp@cavium.com>
Signed-off-by: Duane Grigsby <duane.grigsby@cavium.com>
Signed-off-by: Anil Gurumurthy <anil.gurumurhty@cavium.com>
Signed-off-by: Giridhar Malavali <giridhar.malavali@cavium.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>