Merge pull request #12388 from rgacogne/ddist-async

dnsdist: Implement async processing of queries and responses

diff --cc pdns/dnsdist-lua-actions.cc
Simple merge

diff --cc pdns/dnsdist-tcp.cc
Simple merge

diff --cc pdns/dnsdist.cc
Simple merge

diff --cc pdns/dnsdistdist/doh.cc
Simple merge

diff --cc pdns/lock.hh
Simple merge