Merge branch 'js/avoid-split-sideband-message'

Merge branch 'js/avoid-split-sideband-message'

The side-band status report can be sent at the same time as the
primary payload multiplexed, but the demultiplexer on the receiving
end incorrectly split a single status report into two, which has
been corrected.

* js/avoid-split-sideband-message:
  test-pkt-line: drop colon from sideband identity
  sideband: report unhandled incomplete sideband messages as bugs
  sideband: avoid reporting incomplete sideband messages