MAINTAINERS: Add missing file entries for the USB video class driver

The USB video class driver is missing a few F: entries for files related
to the driver that have been added to the kernel over the years. Add
them.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>