R92C_RF_CHNLBW_LCSTART
rtwn_rf_setbits(sc, 0, R92C_RF_CHNLBW, 0, R92C_RF_CHNLBW_LCSTART);
rtwn_rf_write(sc, 0, R92C_RF_CHNLBW, chnlbw | R92C_RF_CHNLBW_LCSTART);