mapfilter: actually set filterOnly property

cmd/config_mapfilter.go

@@ -29,6 +29,7 @@ var NoMatchError error = errors.New("no match found in mapping")
 func NewDatasetMapFilter(capacity int, filterOnly bool) DatasetMapFilter {
 	return DatasetMapFilter{
 		entries:    make([]datasetMapFilterEntry, 0, capacity),
+		filterOnly: filterOnly,
 	}
 }