remove unnecessary rdkafka flag added by rebase
remove unnecessary rdkafka flag added by rebase

benauthor/pykafka,thedrow/samsa,thedrow/samsa,thedrow/samsa,wikimedia/operations-debs-python-pykafka,benauthor/pykafka,benauthor/pykafka,wikimedia/operations-debs-python-pykafka,wikimedia/operations-debs-python-pykafka