net: make ndo_get_stats64 a void function

The network device operation for reading statistics is only called
in one place, and it ignores the return value. Having a structure
return value is potentially confusing because some future driver could
incorrectly assume that the return value was used.

Fix all drivers with ndo_get_stats64 to have a void function.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index c9414c0..05374fc 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -908,8 +908,8 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu)
 	return ret;
 }
 
-static struct rtnl_link_stats64 *netvsc_get_stats64(struct net_device *net,
-						    struct rtnl_link_stats64 *t)
+static void netvsc_get_stats64(struct net_device *net,
+			       struct rtnl_link_stats64 *t)
 {
 	struct net_device_context *ndev_ctx = netdev_priv(net);
 	int cpu;
@@ -947,8 +947,6 @@ static struct rtnl_link_stats64 *netvsc_get_stats64(struct net_device *net,
 
 	t->rx_dropped	= net->stats.rx_dropped;
 	t->rx_errors	= net->stats.rx_errors;
-
-	return t;
 }
 
 static int netvsc_set_mac_addr(struct net_device *ndev, void *p)