scsi: ses: Fix SAS device detection in enclosure

The call to scsi_is_sas_rphy() needs to be made on the SAS end_device,
not on the SCSI device.

Fixes: 835831c5 ("ses: use scsi_is_sas_rphy instead of is_sas_attached")
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>