change map_lanetoxodr. fix a uturn bug.

src/tool/map_lanetoxodr/mainwindow.cpp

@@ -3806,7 +3806,7 @@ std::vector<geobase> MainWindow::CreateUTurnGeo(double startx, double starty, do
     else
     {
         c2.mfLen = (2.0*M_PI - hdgdiff) * R;
-        c2.mR = R*(-1);
+        c2.mR = R;//R*(-1);
         c3.mfLen = c2.mfLen;
         c3.mR = R;
     }