virtio-balloon: Use virtio_find_vqs() helper

Use the helper virtio_find_vqs().
Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Link: https://lore.kernel.org/r/20210723054259.2779-1-xianting.tian@linux.alibaba.comSigned-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/virtio/virtio_balloon.c

@@ -531,8 +531,8 @@ static int init_vqs(struct virtio_balloon *vb)
 		callbacks[VIRTIO_BALLOON_VQ_REPORTING] = balloon_ack;
 	}
 
-	err = vb->vdev->config->find_vqs(vb->vdev, VIRTIO_BALLOON_VQ_MAX,
-					 vqs, callbacks, names, NULL, NULL);
+	err = virtio_find_vqs(vb->vdev, VIRTIO_BALLOON_VQ_MAX, vqs,
+			      callbacks, names, NULL);
 	if (err)
 		return err;