[media] msp3400: fill in v4l2_tuner based on vt->type field

The vt->type field determines how the msp3400 should fill in the
tuner data, not whether the msp3400 is in radio mode or not.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>