message: Fix for N2N channel key initialization
diff: @@ -162,7 +162,7 @@ namespace ccf
  peer_id,
  (const uint64_t)recv_nonce.nonce);
  - if (recv_nonce.nonce == 1 && next_key)
  + if ((recv_nonce.nonce == 1 || !key) && next_key)
  {
  LOG_TRACE_FMT("Changing to next channel key");
  key.swap(next_key);
  