effects/kscreen: don't use xcb on Wayland

BUG: 450564
FIXED-IN: 5.24.5
(cherry picked from commit db3f2733)

src/effects/kscreen/kscreen.cpp

@@ -44,15 +44,15 @@ namespace KWin
 
 KscreenEffect::KscreenEffect()
     : Effect()
-    , m_atom(effects->announceSupportProperty("_KDE_KWIN_KSCREEN_SUPPORT", this))
+    , m_atom(effects->waylandDisplay() ? XCB_ATOM_NONE : effects->announceSupportProperty("_KDE_KWIN_KSCREEN_SUPPORT", this))
 {
     initConfig<KscreenConfig>();
-    connect(effects, &EffectsHandler::propertyNotify, this, &KscreenEffect::propertyNotify);
-    connect(effects, &EffectsHandler::xcbConnectionChanged, this,
-        [this] {
+    if (!effects->waylandDisplay()) {
+        connect(effects, &EffectsHandler::propertyNotify, this, &KscreenEffect::propertyNotify);
+        connect(effects, &EffectsHandler::xcbConnectionChanged, this, [this]() {
             m_atom = effects->announceSupportProperty(QByteArrayLiteral("_KDE_KWIN_KSCREEN_SUPPORT"), this);
-        }
-    );
+        });
+    }
     reconfigure(ReconfigureAll);
 
     const QList<EffectScreen *> screens = effects->screens();