drm: Mark CONFIG_DRM_HEADER_TEST as BROKEN

The flag got lost during a merge. Add it back.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reported-by: Simona Vetter <simona@ffwll.ch>
Closes: https://people.freedesktop.org/~cbrill/dri-log/?channel=dri-devel&highlight_names=&date=2025-04-10&show_html=true


Fixes: 1afba39f ("Merge drm/drm-next into drm-misc-next")
Acked-by: Simona Vetter <simona@ffwll.ch>
Link: https://lore.kernel.org/r/20250410095014.20471-1-tzimmermann@suse.de