ses: generate KOBJ_CHANGE on enclosure attach

In support of a /dev/disk/by-slot populated with data from the enclosure
and ses modules udev needs notification when the new interface
files/links are available.  Otherwise, any udev rules specified for the
disk cannot assume that the enclosure topology has settled.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/scsi/ses.c

@@ -349,7 +349,8 @@ static int ses_enclosure_find_by_addr(struct enclosure_device *edev,
 		if (scomp->addr != efd->addr)
 			continue;
 
-		enclosure_add_device(edev, i, efd->dev);
+		if (enclosure_add_device(edev, i, efd->dev) == 0)
+			kobject_uevent(&efd->dev->kobj, KOBJ_CHANGE);
 		return 1;
 	}
 	return 0;