ath9k: Set IEEE80211_TX_CTL_RATE_CTRL_PROBE in rate control for probe rate

Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath9k/rc.c

@@ -864,6 +864,8 @@ static void ath_rc_ratefind(struct ath_softc *sc,
 					  rate_table, nrix, 1, 0);
 		ath_rc_rate_set_series(rate_table, &rates[i++], txrc,
 				       try_per_rate, nrix, 0);
+
+		tx_info->flags |= IEEE80211_TX_CTL_RATE_CTRL_PROBE;
 	} else {
 		try_per_rate = (ATH_11N_TXMAXTRY/4);
 		/* Set the choosen rate. No RTS for first series entry. */