V4L/DVB (6967): pvrusb2: add support for Hauppauge WinTV PVR-USB2 Model 75xxx

Create a device description and enable autodetection for
Hauppauge WinTV PVR-USB2 Model 75xxx

Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>