scsi: aacraid: Don't copy uninitialized stack memory to userspace

Both aac_send_raw_srb() and aac_get_hba_info() may copy stack allocated
structs to userspace without initializing all members of these
structs. Clear out this memory to prevent information leaks.

Fixes: 423400e6 ("scsi: aacraid: Include HBA direct interface")
Fixes: c799d519 ("scsi: aacraid: Retrieve HBA host information ioctl")
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>