The Virtual Video Device Driver (aka vivi) is a device that
can be used to:
1) test core v4l functionalities;
2) be a prototype for newer development.
Vivi were developed using the best practices for v4l driver.
When loaded, it provides a video device that generates a
standard color bar, with a timestamp placed at top left corner.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>