Prepare to remove style support again

SineStriker

2023-12-22 a5d13e19dd7f6037e10b649c49805922ae5e0fa6

 src/stylesupport/styleagent_linux.cpp

@@ -7,9 +7,13 @@
    void StyleAgentPrivate::setupSystemThemeHook() {
    }

    void StyleAgentPrivate::removeSystemThemeHook() {
    }

    bool StyleAgentPrivate::updateWindowAttribute(QWindow *window, const QString &key,
                                                  const QVariant &attribute,
                                                  const QVariant &oldAttribute) {
        Q_UNUSED(oldAttribute)
        return false;
    }