fix MTextColumns.link_columns() for DXF < R2018
@@ -310,7 +310,7 @@ class MTextColumns:
def link_columns(self, doc: 'Drawing'):
# DXF R2018+ has no linked MTEXT entities.
- if doc.dxfversion < DXF2018 or not self.linked_handles:
+ if doc.dxfversion >= DXF2018 or not self.linked_handles:
return
db = doc.entitydb
assert db is not None, "entity database not initialized"
