If a client had initiated a stream abort, it will have a call
waiting for a reply in the queue. If more data continues to
arrive on the stream, the abort command could mistakenly get
signalled as complete. Remove the code from async data processing
that looked for waiting calls. Add a sanity check to ensure no
async call can ever be marked as needing a reply

* src/rpc/virnetclient.c: Ensure async data packets can't
  trigger a reply