V4L/DVB (7753): saa7134: fix tuner setup

Tuner setup were happening during i2c attach callback. This means that it would
happen on two conditions:

        1) if tuner module weren't load, it will happen at request_module("tuner");

        2) if tuner is not compiled as a module, or it is already loaded
           (for example, on setups with more than one tuner), it will happen
           when saa7134 registers I2C bus.

Due to that, if tuner were loaded, tuner setup will happen _before_ reading
the proper values at tuner eeprom. Since set_addr refuses to change for a tuner
that were previously defined (except if the tuner_addr is set), this were
making eeprom tuner detection useless.

This patch removes tuner type setup from saa7134-i2c, moving it to the proper
place, after taking eeprom into account.

Reviewed-by: Hermann Pitton <hermann-pitton@arcor.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>