media: zoran: move overlay_settings out of zoran_fh

We need to get rid of zoran_fh, so move the overlay_settings directly in the
zoran structure.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>