drm/udl: Enable damage clipping

Call drm_plane_enable_fb_damage_clips() and give userspace a chance
of minimizing the updated display area.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20220908095115.23396-4-tiwai@suse.de