V4L/DVB (8145a): USB Video Class driver

This driver supports video input devices compliant with the USB Video Class
specification. This means lots of currently manufactured webcams, and probably
most of the future ones.

Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>