data label export does not work with bar charts

Excel just removes the chart during import. Additionally we should work
on only exporting the data label information for points that really
contain data labels.

Change-Id: I80aef8effe27c729feb69c25c319ca129dc961a5

oox/source/export/chartexport.cxx

@@ -1533,7 +1533,7 @@ void ChartExport::exportSeries( Reference< chart2::XChartType > xChartType, sal_
                     // export data labels
                     // Excel does not like our current data label export
                     // for scatter charts
-                    if( eChartType != chart::TYPEID_SCATTER )
+                    if( eChartType != chart::TYPEID_SCATTER && eChartType != chart::TYPEID_BAR )
                         exportDataLabels( uno::Reference< beans::XPropertySet >( aSeriesSeq[nSeriesIdx], uno::UNO_QUERY ), nSeriesLength );
 
                     // export data points