gtp: remove IPv4 and IPv6 header from context object

Based on the idea that ip_tunnel_get_dsfield() provides the tos field
regardless the IP version, use either iph->tos or ipv6_get_dsfield().

This comes in preparation to support for IPv4-in-IPv6-GTP and
IPv6-in-IPv4-GTP.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
1 file changed