scsi: arcmsr: Add support for ARC-1886 series RAID controllers

Add support for ARC-1886 series RAID controllers.

[mkp: apply zeroday build warning fixes]

Link: https://lore.kernel.org/r/78ae03d0ac05054c721cc3a94f41f9e656a5e176.camel@areca.com.tw


Signed-off-by: ching Huang <ching2048@areca.com.tw>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>