scsi: aacraid: Fixed expander hotplug for SMART family

Current driver Hotplug processing code skips over Enclosure channel,
therefore any addition/removal of expander enclosure is not processed.
Additionally device addition code relies on older device type, which
prevents the hotplug of adapter expanders.

Fixed by removing code that skips over Enclosure channels and using the
latest device type for addition or removal or enclosure expanders.

Fixes: 6223a39f (scsi: aacraid: Added support for hotplug)
Signed-off-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Reviewed-by: Dave Carroll <david.carroll@microsemi.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>