master
fix netinet/ether.h for c++
remove indirect use of endian.h from public headers
netinet/if_ether.h: add ETH_P_CFM from linux v5.11
add netinet/igmp.h and multicast groups to netinet/in.h
fix erroneous definition of IN6_IS_ADDR_V4COMPAT
add one more bogus legacy header
add uapi guards for new netinet/ip.h conflict with struct iphdr
update icmphdr struct following linux v4.8
netinet/tcp.h: add tcp_zerocopy_receive fields from linux v5.12
netinet/udp.h: add TCP_ENCAP_ESPINTCP from linux v5.6