V4L/DVB: tuner-types: Add Sony BTF-Pxn01Z tuner type used on GigaPocket cards

Sony makes custome tuners for its GigaPocket line of ivtv based capture
cards.  This adds an entry to the tuner-types list for such tuners.
Parameters are based on experiments by Eric Anderson <rico99@sbcglobal.net>.

Signed-off-by: Andy Walls <awalls@radix.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>