[ath] more updates; please test (especially if you're using an AR9280)

[Adrian Chadd]

I've done a few updates to the ath driver today. In particular, I've
updated the register initvals used to program the AR9280. It's making
my AR9280 here behave a lot better.

I'd appreciate some more before-and-after testing if you use the
AR9280. I'd like to make sure this hasn't introduced any regressions
before I continue more 11n work.

Thanks,


Adrian