Drop COMPAT_INET4 support
Detail: Fill in the sockaddr_in address length. Remove ancient CMHG 5.16 support. Use agnostic TCPIPLibs: include path, case correct CMHG, so CI works. Admin: Submission for TCP/IP bounty.
Detail: Fill in the sockaddr_in address length. Remove ancient CMHG 5.16 support. Use agnostic TCPIPLibs: include path, case correct CMHG, so CI works. Admin: Submission for TCP/IP bounty.