ath9k_hw: Cleanup MCI bits from hw.h

This patch moves all the MCI-specific declarations that have been
dumped unceremoniously in hw.h to ar9003_mci.h

Signed-off-by: Sujith Manoharan <c_manoha@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>