Merge pull request #14495 from rgacogne/ddist-latency-race

dnsdist: Use atomic variables for the per-protocol latencies

diff --cc pdns/dnsdistdist/dnsdist-carbon.cc
Simple merge

diff --cc pdns/dnsdistdist/dnsdist-web.cc
Simple merge

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

diff --cc pdns/dnsdistdist/dnsdist.hh
Simple merge