src/xvba_video_glx.c: Do not change surface status in query_surface_status_glx() function

The function query_surface_status_glx() changes the surface status. This looks
very suspicious and might be even a design error.

src/xvba_video_glx.c

@@ -2086,7 +2086,6 @@ query_surface_status_glx(
             continue;
         if (obj_output->va_surface_status != VASurfaceDisplaying)
             continue;
-        obj_output->va_surface_status = VASurfaceReady;
 
         /* Make sure all pending OpenGL commands have completed */
         GLContextState old_cs;