ath9k: fix retry chain initialization in tx99 code

Initialize first chain attempt counter to 1 in ath9k_build_tx99_skb().
Otherwise multi-retry chain is initialized to {idx,count} = {-1, 0} in
rate_control_fill_sta_table() and tx99 transmission rate is not configured in
rate_control_apply_mask() since first chain idx is set to -1

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/tx99.c

@@ -76,6 +76,7 @@ static struct sk_buff *ath9k_build_tx99_skb(struct ath_softc *sc)
 	tx_info->band = hw->conf.chandef.chan->band;
 	tx_info->flags = IEEE80211_TX_CTL_NO_ACK;
 	tx_info->control.vif = sc->tx99_vif;
+	tx_info->control.rates[0].count = 1;
 
 	memcpy(skb->data + sizeof(*hdr), PN9Data, sizeof(PN9Data));