net: add netdev_lockdep_set_classes() helper

It is time to add netdev_lockdep_set_classes() helper
so that lockdep annotations per device type are easier to manage.

This removes a lot of copies and missing annotations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_eth.c b/net/l2tp/l2tp_eth.c
index c00d72d..57fc5a4 100644
--- a/net/l2tp/l2tp_eth.c
+++ b/net/l2tp/l2tp_eth.c
@@ -67,9 +67,6 @@
 	return net_generic(net, l2tp_eth_net_id);
 }
 
-static struct lock_class_key l2tp_eth_tx_busylock;
-static struct lock_class_key l2tp_qdisc_running_key;
-
 static int l2tp_eth_dev_init(struct net_device *dev)
 {
 	struct l2tp_eth *priv = netdev_priv(dev);
@@ -77,8 +74,7 @@
 	priv->dev = dev;
 	eth_hw_addr_random(dev);
 	eth_broadcast_addr(dev->broadcast);
-	dev->qdisc_tx_busylock = &l2tp_eth_tx_busylock;
-	dev->qdisc_running_key = &l2tp_qdisc_running_key;
+	netdev_lockdep_set_classes(dev);
 
 	return 0;
 }