[PATCH 2/2] bridge: fix compile error when compiling without IPv6 support

Some fields in "struct net_bridge" aren't available when compiling the kernel without IPv6 support. Therefore adding a check/macro to skip the complaining code sections in that case. Introduced by 2cd4143192e8c60f66cb32c3a30c76d0470a372d ("bridge: memorize and export selected IGMP/MLD querier

[PATCH 2/2] bridge: fix compile error when compiling without IPv6 support

Some fields in struct net_bridge aren't available when compiling the kernel without IPv6 support. Therefore adding a check/macro to skip the complaining code sections in that case. Introduced by 2cd4143192e8c60f66cb32c3a30c76d0470a372d (bridge: memorize and export selected IGMP/MLD querier port)