md: report device as congested when suspended

This should writeback from coming when the device is temporarily
suspended.

Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 94c21c1..dcbf9d35 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -199,6 +199,9 @@
 	multipath_conf_t *conf = mddev->private;
 	int i, ret = 0;
 
+	if (mddev_congested(mddev, bits))
+		return 1;
+
 	rcu_read_lock();
 	for (i = 0; i < mddev->raid_disks ; i++) {
 		mdk_rdev_t *rdev = rcu_dereference(conf->multipaths[i].rdev);