[media] cx231xx: fixup video grabber board profile

The video grabber reference design (Veyron) does not have a tuner input, so
do not have it defined in the board profile.

Signed-off-by: Devin Heitmueller <dheitmueller@hauppauge.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>