V4L/DVB (3265): Add count to tunertype struct

The tuner_params element is an array of undefined length,
with each array member being a set of parameters for each
video standard type.
The number of members in the tuner_params array
will be stored in tuners[]->count

Signed-off-by: Michael Krufky <mkrufky@m1k.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>