[media] tuner-core: dead code removal

Remove the now obsolete set_freq. Also merge set_addr and set_type_addr.

In the past, it used to have two different setup calls, one to set just
the tuner type to any tuner found, and another to set the type only if
the address matches. Those two internal calls were grouped together,
but the functions weren't merged, making the code uglier.

No functional changes are done in this patch.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>