message: [netprocessing] disconnect node that sends filterclear
  nodes not serving bloomfilters should disconnect peers
  that send filterclear, just like filteradd and filterload
  nodes that want to enable/disable txrelay should use
  feefilter
diff: @@ -3653,13 +3653,15 @@ bool ProcessMessage(CNode& pfrom, const std::string& msg_type, CDataStream& vRec
  }
  if (msg_type == NetMsgType::FILTERCLEAR) {
  + if (!(pfrom.GetLocalServices() & NODE_BLOOM)) {
  + pfrom.fDisconnect = true;
  + return true;
  + }
  if (pfrom.m_tx_relay == nullptr) {
  return true;
  }
  LOCK(pfrom.m_tx_relay->cs_filter);
  - if (pfrom.GetLocalServices() & NODE_BLOOM) {
  pfrom.m_tx_relay->pfilter = nullptr;
  - }
  pfrom.m_tx_relay->fRelayTxes = true;
  return true;
  }
  