message: [PoS] Allign ComputeStakeModifier (v2) to nHeight logic
  [PoS] cleaning not used stakeTargetHit method + fixing bad nHeight in
  the new compute modifier method.
diff: @@ -122,7 +122,7 @@ uint256 ComputeStakeModifier(const CBlockIndex* pindexPrev, const uint256& kerne
  ss << kernel;
  // switch with old modifier on upgrade block
  - if (pindexPrev->nStakeModifierV2 == uint256() && pindexPrev->nStakeModifier)
  + if (!Params().IsStakeModifierV2(pindexPrev->nHeight + 1))
  ss << pindexPrev->nStakeModifier;
  else
  ss << pindexPrev->nStakeModifierV2;
  @@ -271,16 +271,6 @@ bool GetKernelStakeModifier(uint256 hashBlockFrom, uint64_t& nStakeModifier, int
  return true;
  }
  -//test hash vs target
  -bool stakeTargetHit(const uint256& hashProofOfStake, const int64_t& nValueIn, const uint256& bnTargetPerCoinDay)
  -{
  - //get the stake weight - weight is equal to coin amount
  - uint256 bnCoinDayWeight = uint256(nValueIn) / 100;
  -
  - // Now check if proof-of-stake hash meets target protocol
  - return hashProofOfStake < (bnCoinDayWeight * bnTargetPerCoinDay);
  -}
  -
  bool CheckStakeKernelHash(const CBlockIndex* pindexPrev, const unsigned int nBits, CStakeInput* stake, const unsigned int nTimeTx, uint256& hashProofOfStake, const bool fDebug)
  {
  CBlockIndex* pindexfrom = stake->GetIndexFrom();
  @@ -338,7 +328,7 @@ bool Stake(const CBlockIndex* pindexPrev, CStakeInput* stakeInput, unsigned int
  CBlockIndex* pindexFrom = stakeInput->GetIndexFrom();
  if (!pindexFrom || pindexFrom->nHeight < 1) return error("%s : no pindexfrom\n", __func__);
  - const uint32_t nTimeBlockFrom = pindexFrom->GetBlockHeader().GetBlockTime();
  + const uint32_t nTimeBlockFrom = pindexFrom->nTime;
  const int nHeightBlockFrom = pindexFrom->nHeight;
  //check for maturity (min age/depth) requirements
  