A big thanks to @cynthia!
ace828b is also fixing compilation issue on the auth, so maybe I should split that PR.
Perhaps upstream that one to luawrapper even, although I bet we are out of sync already?
dnsdist: Fix compilation on OS X and FreeBSD
dnsdist: Use portable IPPROTO_TCP instead of SOL_TCP for TCP_FASTOPEN
This fixes the compilation on FreeBSD, where IPPROTO_TCP and
TCP_FASTOPEN are defined but SOL_TCP isn't.
The luawrapper fix from ace828b has been moved to #4537.