ath9k: split tid retry packets into a separate queue

Improves packet retry order and helps with further tx queueing
improvements.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index c497d52..2ce79c1 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -241,6 +241,7 @@
 struct ath_atx_tid {
 	struct list_head list;
 	struct sk_buff_head buf_q;
+	struct sk_buff_head retry_q;
 	struct ath_node *an;
 	struct ath_atx_ac *ac;
 	unsigned long tx_buf[BITS_TO_LONGS(ATH_TID_MAX_BUFS)];