dm mpath: enable DM_TARGET_ATOMIC_WRITES

Both the bio- and rq-based paths have no problem supporting REQ_ATOMIC,
so enable DM_TARGET_ATOMIC_WRITES.

Signed-off-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

Author: johnpgarry

drivers/md/dm-mpath.c

@@ -2307,7 +2307,7 @@ static struct target_type multipath_target = {
 	.name = "multipath",
 	.version = {1, 15, 0},
 	.features = DM_TARGET_SINGLETON | DM_TARGET_IMMUTABLE |
-		    DM_TARGET_PASSES_INTEGRITY,
+		    DM_TARGET_PASSES_INTEGRITY | DM_TARGET_ATOMIC_WRITES,
 	.module = THIS_MODULE,
 	.ctr = multipath_ctr,
 	.dtr = multipath_dtr,