[media] rtl28xxu: add RTL2832P + R828D support

RTL2832P is version of RTL2832U with extra TS interface.
As for now, we support only integrated RTL2832 demod.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>