message: Regroup if condition to reduce repetition
diff: @@ -437,8 +437,8 @@ void TileMap::serialize(NAS2D::Xml::XmlElement* element)
  {
  auto& tile = getTile({x, y}, depth);
  if (
  - (depth > 0 && tile.excavated() && tile.empty() && tile.mine() == nullptr) ||
  - (tile.index() == TerrainType::Dozed && tile.empty() && tile.mine() == nullptr)
  + ((depth > 0 && tile.excavated()) || (tile.index() == TerrainType::Dozed)) &&
  + (tile.empty() && tile.mine() == nullptr)
  )
  {
  tiles->linkEndChild(serializeTile(x, y, depth, tile.index()));
  