carl9170_async_regwrite
carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
carl9170_async_regwrite(addr + 4 * i, word);