V4L/DVB (10366): gspca - mr97310a: New subdriver.

This patch adds support for USB webcams based on the MR97310A chip. It was
tested with an Aiptek PenCam VGA+ webcam.

Signed-off-by: Kyle Guinn <elyk03@gmail.com>
Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>