media: rcar-vin/rcar-vin.h: fix kernel-doc formatting

Fix formatting of two enums and one struct.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>