drm/gma500/cdv: Remove unused tv out paths

Afaik tv out is not available on Cedarview and the code isn't doing
anything so remove it.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20210201132617.1233-3-patrik.r.jakobsson@gmail.com