net: make vlan ndo_vlan_rx_[add/kill]_vid return error value

Let caller know the result of adding/removing vlan id to/from vlan
filter.

In some drivers I make those functions to just return 0. But in those
where there is able to see if hw setup went correctly, return value is
set appropriately.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
index d96bfb1..1c2ae11 100644
--- a/drivers/net/vmxnet3/vmxnet3_drv.c
+++ b/drivers/net/vmxnet3/vmxnet3_drv.c
@@ -1926,7 +1926,7 @@
 }
 
 
-static void
+static int
 vmxnet3_vlan_rx_add_vid(struct net_device *netdev, u16 vid)
 {
 	struct vmxnet3_adapter *adapter = netdev_priv(netdev);
@@ -1943,10 +1943,12 @@
 	}
 
 	set_bit(vid, adapter->active_vlans);
+
+	return 0;
 }
 
 
-static void
+static int
 vmxnet3_vlan_rx_kill_vid(struct net_device *netdev, u16 vid)
 {
 	struct vmxnet3_adapter *adapter = netdev_priv(netdev);
@@ -1963,6 +1965,8 @@
 	}
 
 	clear_bit(vid, adapter->active_vlans);
+
+	return 0;
 }