scsi: aacraid: remove unused variables dev and cpu

Variables dev and cpu are not being used and are redundant and hence can
be removed.

Cleans up clang warnings:
warning: variable 'dev' set but not used [-Wunused-but-set-variable]
warning: variable 'cpu' set but not used [-Wunused-but-set-variable]

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>