dm kcopyd: clean interface

Clean up the kcopyd interface to prepare for publishing it in include/linux.

Signed-off-by: Heinz Mauelshagen <hjm@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/drivers/md/dm-snap.h b/drivers/md/dm-snap.h
index 434d1db..24f9fb7 100644
--- a/drivers/md/dm-snap.h
+++ b/drivers/md/dm-snap.h
@@ -169,7 +169,7 @@
 	/* The on disk metadata handler */
 	struct exception_store store;
 
-	struct kcopyd_client *kcopyd_client;
+	struct dm_kcopyd_client *kcopyd_client;
 
 	/* Queue of snapshot writes for ksnapd to flush */
 	struct bio_list queued_bios;