fix build on Qt 6.4
Qt 6.4 introduced some changes and it broke qt6 build on master. This patch resolves build errors I mentioned in https://bugs.kde.org/show_bug.cgi?id=456289#c57 and the IRC channel.
Qt 6.4 introduced some changes and it broke qt6 build on master. This patch resolves build errors I mentioned in https://bugs.kde.org/show_bug.cgi?id=456289#c57 and the IRC channel.