xwayland: Don't take buffer release queue into account for frame timer
The buffer release queue has two kinds of entries: * Pending async flips. * Completed flips waiting for their buffer to be released by the Wayland compositor. xwl_present_timer_callback neither completes async flips nor releases buffers, so the timer isn't needed for the buffer release queue.
xwl_window-present_flipped in 57 seconds (queued for 3 seconds)1 job for