net/dummy: Move stats allocation to core

With commit 34d21de9 ("net: Move {l,t,d}stats allocation to core and
convert veth & vrf"), stats allocation could be done on net core instead
of this driver.

With this new approach, the driver doesn't have to bother with error
handling (allocation failure checking, making sure free happens in the
right spot, etc). This is core responsibility now.

Move dummy driver to leverage the core allocation.
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Breno Leitao <leitao@debian.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/dummy.c

@@ -67,19 +67,12 @@ static netdev_tx_t dummy_xmit(struct sk_buff *skb, struct net_device *dev)
 
 static int dummy_dev_init(struct net_device *dev)
 {
-	dev->lstats = netdev_alloc_pcpu_stats(struct pcpu_lstats);
-	if (!dev->lstats)
-		return -ENOMEM;
+	dev->pcpu_stat_type = NETDEV_PCPU_STAT_LSTATS;
 
 	netdev_lockdep_set_classes(dev);
 	return 0;
 }
 
-static void dummy_dev_uninit(struct net_device *dev)
-{
-	free_percpu(dev->lstats);
-}
-
 static int dummy_change_carrier(struct net_device *dev, bool new_carrier)
 {
 	if (new_carrier)
@@ -91,7 +84,6 @@ static int dummy_change_carrier(struct net_device *dev, bool new_carrier)
 
 static const struct net_device_ops dummy_netdev_ops = {
 	.ndo_init		= dummy_dev_init,
-	.ndo_uninit		= dummy_dev_uninit,
 	.ndo_start_xmit		= dummy_xmit,
 	.ndo_validate_addr	= eth_validate_addr,
 	.ndo_set_rx_mode	= set_multicast_list,