ath: fix sysctl cleanup on detach

[Antonio Huete Jimenez]

Committed, thanks!

2010/4/17 Rui Paulo <rpaulo at gmail.com>:
> On 16 Apr 2010, at 19:11, Johannes Hofmann wrote:
>
>> Currently ath does not properly remove sysctl's on detach causing
>> panics when doing "sysctl -a" after unloading the module.
>> This patch fixes the issue:
>> http://leaf.dragonflybsd.org/~hofmann/ath_sysctl_detach.diff
>
> This can be committed. Thanks.
>
> Regards,
> --
> Rui Paulo
>