qa/1321: wait for QA pmlogger to finish after signal
qa/1321: wait for QA pmlogger to finish after signal

Otherwise we potentailly race with the pmlogger sanity checking in
check.callback.

adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp,adfernandes/pcp