coverity#984099: Unitialized scalar field

Change-Id: I9938ffebca054744a6a1e333df3933a3633ea8d3
Reviewed-on: https://gerrit.libreoffice.org/2318Reviewed-by: Thomas Arnhold <thomas@arnhold.org>
Tested-by: Thomas Arnhold <thomas@arnhold.org>

oox/source/vml/vmltextbox.cxx

@@ -41,8 +41,12 @@ TextPortionModel::TextPortionModel( const TextFontModel& rFont, const OUString&
 }
 
 TextBox::TextBox(ShapeTypeModel& rTypeModel)
-    : mrTypeModel(rTypeModel),
-    borderDistanceSet( false )
+    : mrTypeModel(rTypeModel)
+    , borderDistanceSet( false )
+    , borderDistanceLeft(0)
+    , borderDistanceTop(0)
+    , borderDistanceRight(0)
+    , borderDistanceBottom(0)
 {
 }