egl/wayland: Flush the wl_display at the end of SwapBuffers

We would like the compositor to receive the commited buffer
as soon as possible, so it has the time to treat it, and
release old ones. We shouldn't rely on the client
to flush the queue for us.

Signed-off-by: Axel Davy <axel.davy@ens.fr>
Cc: "10.0" mesa-stable@lists.freedesktop.org

src/egl/drivers/dri2/platform_wayland.c

@@ -615,6 +615,8 @@ dri2_swap_buffers_with_damage(_EGLDriver *drv,
    (*dri2_dpy->flush->flush)(dri2_surf->dri_drawable);
    (*dri2_dpy->flush->invalidate)(dri2_surf->dri_drawable);
 
+   wl_display_flush(dri2_dpy->wl_dpy);
+
    return EGL_TRUE;
 }