Always hide select button on binary cell when the field is readonly

Closes #13714
(grafted from b9da884274caa17aa9c7e42891f0019a9dff9b89)

--HG--
branch : 6.0

tryton/tryton/gui/window/view_form/view/list_gtk/widget.py

@@ -705,7 +705,7 @@ class _BinarySelect(_BinaryIcon):
         invisible = field.get_state_attrs(record).get('invisible', False)
         readonly = self.attrs.get('readonly',
             field.get_state_attrs(record).get('readonly', False))
-        if readonly and size:
+        if readonly or size:
             cell.set_property('visible', False)
         else:
             cell.set_property('visible', not invisible)