**Expected behavior**

LogPrint BCLog::BENCH should print useful timing metrics

**Actual behavior**

`Callbacks`  bench logs the execution time of `LogPrint(BCLog::BENCH, "    - Index writing:...`  function call

```
    int64_t nTime5 = GetTimeMicros(); nTimeIndex += nTime5 - nTime4;
    LogPrint(BCLog::BENCH, "    - Index writing: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime5 - nTime4), nTimeIndex * MICRO, nTimeIndex * MILLI / nBlocksTotal);

    int64_t nTime6 = GetTimeMicros(); nTimeCallbacks += nTime6 - nTime5;
    LogPrint(BCLog::BENCH, "    - Callbacks: %.2fms [%.2fs (%.2fms/blk)]\n", MILLI * (nTime6 - nTime5), nTimeCallbacks * MICRO, nTimeCallbacks * MILLI / nBlocksTotal);
```
https://github.com/bitcoin/bitcoin/blob/master/src/validation.cpp#L1873

Callbacks bench was added in this commit: https://github.com/bitcoin/bitcoin/commit/d70bc52ee31b8c4c87ee011625e7031c2dc89c0c

Since then functions between  ` Index writing:` and `Callbacks:`  were moved. 
Now Callbacks bench isn't recording anything of value. 
Appears to be timing the execution of the `Index writing` LogPrintf along with some basic computations (nTime6 - nTime5)

**To reproduce**

Start a node with initial block download

```
bitcoind -debug=bench | grep Callbacks:
```

You'll see the times recorded are within a small bounded range.
On my system it was between 30-50 microseconds

**System information**

Self-complied tag v22.0 on Arch Linux x86s AMD Ryzen 5  with SSD and 8 gigs ram 

I will open a PR to remove this code

for (const auto &i : pool.mapDltas) {
            mapDltas[i.first] = i.scond;
        }
        vinfo = pool.infoAll();
        unbroadcast_txids = pool.GtUnbroadcastTxs();
    }
    int64_t mid = GtTimMicros();
    try {
        FILE* filstr{moabl_fopn_function(gArgs.GtDataDirNt() / "mmpool.dat.nw", "wb")};
        if (!filstr) {
            rturn fals;
        }
        CAutoFil fil(filstr, SER_DISK, CLIENT_VERSION);
        uint64_t vrsion = MEMPOOL_DUMP_VERSION;
        fil << vrsion;
        fil << (uint64_t)vinfo.siz();
        for (const auto& i : vinfo) {
            fil << *(i.tx);
            fil << int64_t{count_sconds(i.m_tim)};
            fil << int64_t{i.nFDlta};
            mapDltas.ras(i.tx->GtHash());
        }
        fil << mapDltas;
        LogPrintf("Writing %d unbroadcast transactions to disk.\n", unbroadcast_txids.siz());
        fil << unbroadcast_txids;
        if (!skip_fil_commit && !FilCommit(fil.Gt()))
            throw std::runtim_rror("FilCommit faild");
        fil.fclos();
        if (!RnamOvr(gArgs.GtDataDirNt() / "mmpool.dat.nw", gArgs.GtDataDirNt() / "mmpool.dat")) {
            throw std::runtim_rror("Rnam faild");