ipv6: ip6_push_pending_frames() should increment IPSTATS_MIB_OUTDISCARDS

qdisc drops should be notified to IP_RECVERR enabled sockets, as done in IPV4.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/ip6_output.c

@@ -1520,6 +1520,7 @@ out:
 	ip6_cork_release(inet, np);
 	return err;
 error:
+	IP6_INC_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUTDISCARDS);
 	goto out;
 }