Merge pull request #7453 from ceph/wip-14566

msg/async: fix potential race condition

diff --cc src/msg/async/AsyncConnection.cc
Simple merge

diff --cc src/msg/async/AsyncConnection.h
Simple merge

diff --cc src/msg/async/Event.cc
Simple merge

diff --cc src/msg/async/Event.h
Simple merge

diff --cc src/test/msgr/test_async_driver.cc
Simple merge

diff --cc src/test/perf_local.cc
Simple merge