net: bridge: add missing counters to ndo_get_stats64 callback

In br_forward.c and br_input.c fields dev->stats.tx_dropped and
dev->stats.multicast are populated, but they are ignored in
ndo_get_stats64.

Fixes: 28172739f0 ("net: fix 64 bit counters on 32 bit arches")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Link: https://lore.kernel.org/r/58ea9963-77ad-a7cf-8dfd-fc95ab95f606@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/bridge/br_device.c

@@ -207,6 +207,7 @@ static void br_get_stats64(struct net_device *dev,
 {
 	struct net_bridge *br = netdev_priv(dev);
 
+	netdev_stats_to_stats64(stats, &dev->stats);
 	dev_fetch_sw_netstats(stats, br->stats);
 }