scsi: aacraid: Remove an unused function

This was detected by building the kernel with clang and W=1.

Link: https://lore.kernel.org/r/20210415220826.29438-7-bvanassche@acm.org


Cc: aacraid@microsemi.com
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>