fix bug in secop.gui.valuewidgets

- fix ArrayOf maxlen instead of maxsize
- marked missing NoneOr widget as TODO
  (Remark: there are quite a lot of other things in cfg-editor to fix)

Change-Id: I3a8b2f650cca45dae4f87ba63c70ae58ca49ce42
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/23037
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop/gui/valuewidgets.py

@@ -201,7 +201,7 @@ class ArrayWidget(QGroupBox):
 
         self.layout = QVBoxLayout()
         self.subwidgets = []
-        for _ in range(datatype.maxsize):
+        for _ in range(datatype.maxlen):
             w = get_widget(self.datatype, readonly=readonly, parent=self)
             self.layout.addWidget(w)
             self.subwidgets.append(w)
@@ -228,7 +228,7 @@ def get_widget(datatype, readonly=False, parent=None):
      StructOf: StructWidget,
      ArrayOf: ArrayWidget,
     }.get(datatype.__class__)(datatype, readonly, parent)
-
+# TODO: handle NoneOr
 
 class msg(QDialog):
     def __init__(self, stuff, parent=None):