vhost_net: make vhost_zerocopy_signal_used() return void

None of its caller use its return value, so let it return void.

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 969a859..280ee66 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -276,8 +276,8 @@
  * of used idx. Once lower device DMA done contiguously, we will signal KVM
  * guest used idx.
  */
-static int vhost_zerocopy_signal_used(struct vhost_net *net,
-				      struct vhost_virtqueue *vq)
+static void vhost_zerocopy_signal_used(struct vhost_net *net,
+				       struct vhost_virtqueue *vq)
 {
 	struct vhost_net_virtqueue *nvq =
 		container_of(vq, struct vhost_net_virtqueue, vq);
@@ -297,7 +297,6 @@
 	}
 	if (j)
 		nvq->done_idx = i;
-	return j;
 }
 
 static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success)