drm/msm: dpu: Don't queue the frame_done watchdog for cursor

drm/msm: dpu: Don't queue the frame_done watchdog for cursor

In the case of an async/cursor update, we don't wait for the frame_done
event, which means handle_frame_done is never called, and the frame_done
watchdog isn't canceled. Currently, this results in a frame_done timeout
every time the cursor moves without a synchronous frame following it up
before the timeout expires. Since we don't wait for frame_done, and
don't handle it, we shouldn't modify the watchdog.

Reviewed-by: Fritz Koenig <frkoenig@google.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20190128204306.95076-4-sean@poorly.run
Signed-off-by: Rob Clark <robdclark@chromium.org>