message: Fix unsigned integer overflow in LoadMempool
diff: @@ -4439,7 +4439,8 @@ bool LoadMempool(CTxMemPool& pool, CChainState& active_chainstate, FopenFn mocka
  }
  uint64_t num;
  file >> num;
  - while (num--) {
  + while (num) {
  + --num;
  CTransactionRef tx;
  int64_t nTime;
  int64_t nFeeDelta;
  