Revert "Fix build with Qt 5.15"
Summary: This reverts commit 3a5aca82527ec45d22d09e220ff3ff00a42971d2.
Reviewers: broulik
Reviewed By: broulik
Subscribers: broulik, plasma-devel
Tags: Plasma
Differential Revision: https://phabricator.kde.org/D28481