dm: trigger change uevent on rename

Insert a missing KOBJ_CHANGE notification when a device is renamed.

Cc: Scott James Remnant <scott@ubuntu.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

drivers/md/dm.h

@@ -187,4 +187,6 @@ union map_info *dm_get_mapinfo(struct bio *bio);
 int dm_open_count(struct mapped_device *md);
 int dm_lock_for_deletion(struct mapped_device *md);
 
+void dm_kobject_uevent(struct mapped_device *md);
+
 #endif