V4L/DVB (6468): tda8290: auto-detect tda8290 or tda8295

Consolidate tda8290_attach() and tda8295_attach() into a single function,
tda829x_attach(), which will detect chip combinations tda8290 or tda8295 with
tda8275, tda8275a or tda18271.

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