IPv4 GSO packets may get processed in ovs_skb_network_trim(),
and we need to use skb_ip_totlen() to get iph totlen.
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Reviewed-by: NAaron Conole <aconole@redhat.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NJakub Kicinski <kuba@kernel.org>