qmlui: fix crash on shared pointer deletion
qmlui: fix crash on shared pointer deletion

kripton/qlcplus,sbenejam/qlcplus,sbenejam/qlcplus,mcallegari/qlcplus,mcallegari/qlcplus,kripton/qlcplus,plugz/qlcplus,sbenejam/qlcplus,mcallegari/qlcplus,sbenejam/qlcplus,kripton/qlcplus,plugz/qlcplus,plugz/qlcplus,kripton/qlcplus,kripton/qlcplus,mcallegari/qlcplus,sbenejam/qlcplus,plugz/qlcplus,kripton/qlcplus,plugz/qlcplus,mcallegari/qlcplus,plugz/qlcplus,mcallegari/qlcplus,sbenejam/qlcplus,mcallegari/qlcplus,sbenejam/qlcplus,plugz/qlcplus,kripton/qlcplus