add a fixme about bogus section handling

the filtermodel only sorts by timestamp of the device, not the actual
types we visualize so you can conceivably have sections appear multiple
times

```
Drives
--------
/dev/sdc

Media Player
------------
/usb/123

Drives
-------
/dev/sdd
```

applets/devicenotifier/package/contents/ui/FullRepresentation.qml

@@ -148,6 +148,8 @@ PlasmaExtras.Representation {
             //acceptable since one doesn't have a billion of devices
             cacheBuffer: 1000
 
+            // FIXME: the model is sorted by timestamp, not type, this results in sections possibly getting listed
+            //   multiple times
             section {
                 property: "Type Description"
                 delegate: Item {