scsi: aacraid: Rework aac_src_restart

Removed switch case and replaced with if mask checks. Moved KERNEL_PANIC
check to when bled is less than 0.

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>