scsi: aacraid: Using single reset mask for IOP reset

The driver can now trigger IOP reset with a single reset mask. Removed
code that retrieves a reset_mask from the firmware.

Signed-off-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Reviewed-by: David Carroll <david.carroll@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>