tdf#96662, only use the crossBetween="midCat" for line and scatter chart

Change-Id: Id2be263daf2c5a9f2d69ed50b79ac029143f02ca
Reviewed-on: https://gerrit.libreoffice.org/29080Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
Tested-by: Markus Mohrhard <markus.mohrhard@googlemail.com>

oox/source/export/chartexport.cxx

@@ -2864,7 +2864,8 @@ void ChartExport::_exportAxis(
     // category axis, so we ideally need an algorithm that decides
     // when to map the crossing to the tick mark and when to the
     // middle of the category
-    if (nAxisType == XML_valAx)
+    sal_Int32 nChartType = getChartType();
+    if (nAxisType == XML_valAx && (nChartType == chart::TYPEID_LINE || nChartType == chart::TYPEID_SCATTER))
     {
         pFS->singleElement( FSNS( XML_c, XML_crossBetween ),
                 XML_val, "midCat",