[kde-base/plasma-workspace] Depends on qtquickcontrols[widgets]

The plasmashell configuration dialog requires at least WidgetMessageDialog.qml
which is provided by dev-qt/qtquickcontrols once it is built with the 'widgets'
USE flag enabled.

Package-Manager: portage-2.2.10
Merge pull request #32 from eliasp/plasma-workspace-qtquickcontrols-widgets

[kde-base/plasma-workspace] Depends on qtquickcontrols[widgets]