scsi: smartpqi: add ofa support

- when OFA event occurs, driver will stop traffic to RAID/HBA path. Driver
  waits for all the outstanding requests to complete.
- Driver sends OFA event acknowledgment to firmware.
- Driver will wait until the new firmware is up and running.
- Driver will free up the resources.
- Driver calls SIS/PQI initialization and rescans the device list.
- Driver will resume the traffic to RAID/HBA path.

Reviewed-by: Murthy Bhat <murthy.bhat@microsemi.com>
Signed-off-by: Mahesh Rajashekhara <mahesh.rajashekhara@microsemi.com>
Signed-off-by: Don Brace <don.brace@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>