ath6kl: kill Android specific code

To get upstream we can't use out of tree defines, kill
all the androidisms. ath6kl won't be usable on Android
unless external patches are supported later or Android
gets their shit together and gets all their crap upstream.

Cc: Naveen Singh <nsingh@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>