Add a pre_remove handler that unregisters the video_idle cyclic when
the last video device is removed. This ensures the cyclic won't run
after driver model is reinitialised by the test framework.
This complements the uclass_find() fix by properly cleaning up the
cyclic registration rather than just gracefully handling the orphaned
state.
Co-developed-by: Claude <noreply@anthropic.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
c2ebe820ed