message: [Wallet] Fix autocombine
  small nit, use while instead of empty for
  use nTotalRewardsValue instead of vecSend[0].second to check value is
  above threshold
diff: @@ -2720,7 +2720,7 @@ bool CWallet::CreateTransaction(const vector<pair<CScript, CAmount> >& vecSend,
  scriptChange = GetScriptForDestination(coinControl->destChange);
  vector<CTxOut>::iterator it = txNew.vout.begin();
  - for (; it != txNew.vout.end();) {
  + while (it != txNew.vout.end()) {
  if (scriptChange == it->scriptPubKey) {
  it->nValue += nChange;
  nChange = 0;
  @@ -4075,7 +4075,7 @@ void CWallet::AutoCombineDust()
  }
  //we don't combine below the threshold unless the fees are 0 to avoid paying fees over fees over fees
  - if (vecSend[0].second < nAutoCombineThreshold * COIN && nFeeRet > 0)
  + if (nTotalRewardsValue < nAutoCombineThreshold * COIN && nFeeRet > 0)
  continue;
  if (!CommitTransaction(wtx, keyChange)) {
  