`processor.run` will forever loop complaining the tx control channel is closed

[mvachhar]

If the transmitter to the ConfigProcessor's control channel is closed (all transmitters on the channel close), the run method gets stuck forever looping on an error complaining that all tx channels were closed, spamming the log. If all tx channels are closed, the run method should return, perhaps with an error. But it certainly should not continue to run since it can no longer perform useful work.