[media] gspca: Add new vicam subdriver

This is a complete rewrite of the old v4l1 vicam subdriver, featuring
multiple resolutions, gain + exposure control and still has less code.

Oh and it is a v4l2 driver rather then v4l1 ofcourse :)

Many thanks to Devin Heitmueller <dheitmueller@kernellabs.com> for
donating his 3com homeconnect to me, which made this rewrite possible.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>