Assure wayland output interface creation path
Summary:
The Wayland and XDG output interfaces are created or destroyed when the
output is en- or disabled. This follows a clear path of dependencies and
we should not check if this is indeed the case but instead assert on it.
Test Plan: Nested Wayland and Drm sessions.
Reviewers: KWin, zzag
Reviewed By: KWin, zzag
Subscribers: kwin
Tags: KWin
Differential Revision: https://phabricator.kde.org/D23540