ath9k: make ath_frame_info fit into reduced-size rate_driver_data

pre-requisite to shrink size of ieee80211_tx_info which in turn is
needed to shrink skb->cb to 40 bytes again.
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/ath/ath9k/ath9k.h

@@ -184,12 +184,12 @@ struct ath_frame_info {
 	struct ath_buf *bf;
 	u16 framelen;
 	s8 txq;
-	enum ath9k_key_type keytype;
 	u8 keyix;
 	u8 rtscts_rate;
 	u8 retries : 7;
 	u8 baw_tracked : 1;
 	u8 tx_power;
+	enum ath9k_key_type keytype:2;
 };
 
 struct ath_rxbuf {