For every peer expose through `getpeerinfo` RPC whether or not we selected them as HB peers, and whether or not they selected us as HB peers.

Suggestion by @gmaxwell.
addr.nTime = nNow - 5 * 24 * 60 * 60;
            pfrom.AddAddressKnown(addr);
            if (m_banman && (m_banman->IsDiscouraged(addr) || m_banman->IsBanned(addr))) {
                
                continue;
            }
            bool fReachable = IsReachable(addr);
            if (addr.nTime > nSince && !pfrom.fGetAddr && vAddr.size() <= 10 && addr.IsRoutable())
            {
                
                RelayAddress(addr, fReachable, m_connman);
            }
            
            if (fReachable)
                vAddrOk.push_back(addr);
        }
        m_connman.AddNewAddresses(vAddrOk, pfrom.addr, 2 * 60 * 60);
        if (vAddr.size() < 1000)
            pfrom.fGetAddr = false;
        if (pfrom.IsAddrFetchConn())
            pfrom.fDisconnect = true;
        return;
    }
    if (msg_type == NetMsgType::SENDHEADERS) {
        LOCK(cs_main);
        State(pfrom.GetId())->fPreferHeaders = true;
        return;
    }
    if (msg_type == NetMsgType::SENDCMPCT) {
        bool fAnnounceUsingCMPCTBLOCK = false;