iptables: Add hack to compile against Econet kernel

Subject: [PATCH] Fix compilation against econet-kernel uapi

Econet kernel patches struct ebt_ip6_info members tclass and protocol from simple uint8_t to be two-element arrays in include/linux/netfilter_bridge/ebt_ip6.h. The same thing goes for struct ebt_vlan_info members id and prio from struct ebt_vlan_info which also have been changed to two-element arrays instead from their uint16_t and uint_8t counterparts. Not unsurprisingly, this causes compilation errors in existing code where values are directly assigned to these members.

It is unclear what the extra-space is being used for by Econet and whether it should be zeroed in the corresponding code or not. Furthermore, it is unclear whether the corresponding ebtables/iptables functionality is even used in IOWRT. For now, this patch will make the code compile but does not make any guarantee on runtime-functionality.

Most probably, further work is necessary, to fix this the proper way!