[media] tuner-core: Change config from unsigned int to void *

config looks like a hack that was added to tuner-core to allow some
configuration of TDA8290 tuner (it's not used by any other driver).
But with the new configuration options of tda8290 driver (no_i2c_gate
and std_map), it's no longer sufficient.
Change config to be void * instead, which allows passing tuner-dependent
config struct to drivers.
Also update saa7134 driver to reflect this change (no other driver uses this).

Signed-off-by: Ondrej Zary <linux@rainbow-software.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>