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>

drivers/md/linear.c

@@ -108,6 +108,9 @@ static int linear_congested(void *data, int bits)
 	linear_conf_t *conf;
 	int i, ret = 0;
 
+	if (mddev_congested(mddev, bits))
+		return 1;
+
 	rcu_read_lock();
 	conf = rcu_dereference(mddev->private);