Fix obtaining wl_surface from WId
f2f14df4 ported from KWayland::Surface::fromQtWinId to QWindow::fromWinId, but QWindow::fromWinId doesn't work on Wayland.
Instead copy the implementation from KWayland and use that
f2f14df4 ported from KWayland::Surface::fromQtWinId to QWindow::fromWinId, but QWindow::fromWinId doesn't work on Wayland.
Instead copy the implementation from KWayland and use that