Fix copy/paste error with received total

The sent and received byte totals in the statistics data are identical, due to a copy/paste error.
This change fixes that.

Example of the problem:
```javascript
{
    "tcp": {
      ...
      "receivedBytesSinceLastRun": 22,
      "receivedBytesTotal": 165092,
      "sentBytesSinceLastRun": 15038,
      "sentBytesTotal": 165092
    }
   ...
}
```