V4L/DVB (12300): bttv: fix regression: tvaudio must be loaded before tuner

Both tvaudio and the tuner share i2c address 0x42. The tvaudio module can
check whether it really is a tda9840, but the tuner can't. So the tvaudio
module must be loaded before the tuner module. This was also the case for
2.6.29, but the order was swapped in 2.6.30.

Thanks to Krzysztof Grygiencz for reporting and testing this.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>