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.
const CBlockIndex *pindexWalk = pindexLast;
            
            while (pindexWalk && !::ChainActive().Contains(pindexWalk) && vToFetch.size() <= MAX_BLOCKS_IN_TRANSIT_PER_PEER) {
                if (!(pindexWalk->nStatus & BLOCK_HAVE_DATA) &&
                        !mapBlocksInFlight.count(pindexWalk->GetBlockHash()) &&
                        (!IsWitnessEnabled(pindexWalk->pprev, m_chainparams.GetConsensus()) || State(pfrom.GetId())->fHaveWitness)) {
                    
                    vToFetch.push_back(pindexWalk);
                }
                pindexWalk = pindexWalk->pprev;
            }
            
            
            
            
            if (!::ChainActive().Contains(pindexWalk)) {
                LogPrint(BCLog::NET, "Large reorg, won't direct fetch to %s (%d)\n",
                        pindexLast->GetBlockHash().ToString(),
                        pindexLast->nHeight);
            } else {
                std::vector<CInv> vGetData;
                
                for (const CBlockIndex *pindex : reverse_iterate(vToFetch)) {
                    if (nodestate->nBlocksInFlight >= MAX_BLOCKS_IN_TRANSIT_PER_PEER) {
                        
                        break;
                    }
                    uint32_t nFetchFlags = GetFetchFlags(pfrom);
                    vGetData.push_back(CInv(MSG_BLOCK | nFetchFlags, pindex->GetBlockHash()));
                    MarkBlockAsInFlight(m_mempool, pfrom.GetId(), pindex->GetBlockHash(), pindex);