In listview mode use the default implemention of moveCursor
Review Request #128852 - Created Sept. 6, 2016 and submitted
KCategorizedView overrides the moveCursor to handle moving the cursor in the grid; however it's own implementation doesn't handle key up/down when it's not in an exact grid mode; which happens to also include list mode. In this case we don't need anything custom and the QListView implementation works perfectly. This fixes KPluginSelector keyboard navigation.