ath9k: Remove incorrect register macros

These macros are applicable to pre-AR9003 chips
and the addresses are different for the AR9003
family. Since they are unused anyway, remove them.

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>