3b869d8f71
echoping is non-default optional but very useful dependency of the SmokePing (net-mgmt/smokeping). I use the software and will maintain the port. While here, make it possible to build echoping with GNU dns/libidn2 instead of dns/libidn. For now, still use libidn to preserve POLA. Default build not changed comparing with one before removal, so PORTREVISION not bumped.