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/slip/slip.c b/drivers/net/slip/slip.c
index 9841f3d..08db4d6 100644
--- a/drivers/net/slip/slip.c
+++ b/drivers/net/slip/slip.c
@@ -566,7 +566,7 @@ static int sl_change_mtu(struct net_device *dev, int new_mtu)
 
 /* Netdevice get statistics request */
 
-static struct rtnl_link_stats64 *
+static void
 sl_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
 {
 	struct net_device_stats *devstats = &dev->stats;
@@ -597,7 +597,6 @@ sl_get_stats64(struct net_device *dev, struct rtnl_link_stats64 *stats)
 		stats->collisions     += comp->sls_o_misses;
 	}
 #endif
-	return stats;
 }
 
 /* Netdevice register callback */