message: Fix: Staking maturity check was off by 1 block for XSPEC
diff: @@ -2463,8 +2463,8 @@ bool CTransaction::ConnectInputs(CTxDB& txdb, MapPrevTx inputs, map<uint256, CTx
  if (txPrev.IsCoinBase() || txPrev.IsCoinStake())
  {
  int nSpendDepth;
  - if (IsConfirmedInNPrevBlocks(txindex, pindexBlock, Params().GetStakeMinConfirmations(nTime), nSpendDepth))
  - return error("ConnectInputs() : tried to spend %s at depth %d", txPrev.IsCoinBase() ? "coinbase" : "coinstake", nSpendDepth);
  + if (IsConfirmedInNPrevBlocks(txindex, pindexBlock, Params().GetStakeMinConfirmations(nTime) -1 , nSpendDepth))
  + return error("ConnectInputs() : tried to spend %s at depth %d", txPrev.IsCoinBase() ? "coinbase" : "coinstake", nSpendDepth + 1);
  }
  if (txPrev.vout[prevout.n].IsEmpty())
  