message: Fix ScanForWalletTransactions start_block comment
  Suggested
diff: @@ -1617,10 +1617,11 @@ int64_t CWallet::RescanFromTime(int64_t startTime, const WalletRescanReserver& r
  * from or to us. If fUpdate is true, found transactions that already
  * exist in the wallet will be updated.
  *
  - * @param[in] start_block if not null, the scan will start at this block instead
  - * of the genesis block
  - * @param[in] stop_block if not null, the scan will stop at this block instead
  - * of the chain tip
  + * @param[in] start_block Scan starting block. If block is not on the active
  + * chain, the scan will return SUCCESS immediately.
  + * @param[in] stop_block Scan ending block. If block is not on the active
  + * chain, the scan will continue until it reaches the
  + * chain tip.
  *
  * @return ScanResult returning scan information and indicating success or
  * failure. Return status will be set to SUCCESS if scan was
  