scsi: aacraid: fixed firmware assert issue

Before issuing IOP reset, INTX mode is selected. This is triggering MSGU
lockup and ended in basecode assert. Use DROP_IO command when IOP reset is
sent in preparation for interrupt mode switch.

Link: https://lore.kernel.org/r/1571120524-6037-4-git-send-email-balsundar.p@microsemi.com


Signed-off-by: Balsundar P <balsundar.p@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>