cmake HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H examples

shadowsocks/shadowsocks-libev cmake/configure.cmake :39 

check_include_files(linux/netfilter_ipv6/ip6_tables.h HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H)

ShadowsocksR-Live/shadowsocksr-native cmake/configure.cmake :45 

check_include_files ( "linux/netfilter_ipv6/ip6_tables.h" HAVE_LINUX_NETFILTER_IPV6_IP6_TABLES_H )