ath9k: properly use the mac80211 rate control api

This patch changes ath9k to pass proper MCS indexes and flags
between the RC and the rest of the driver code.
sc->cur_rate_table remains, as it's used by the RC code internally,
but the rest of the driver code no longer uses it, so a potential
new RC for ath9k would not have to update it.

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/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index a22ed76..b126342 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -647,7 +647,7 @@
 u32 ath9k_hw_reverse_bits(u32 val, u32 n);
 bool ath9k_get_channel_edges(struct ath_hw *ah, u16 flags, u16 *low, u16 *high);
 u16 ath9k_hw_computetxtime(struct ath_hw *ah,
-			   const struct ath_rate_table *rates,
+			   u8 phy, int kbps,
 			   u32 frameLen, u16 rateix, bool shortPreamble);
 void ath9k_hw_get_channel_centers(struct ath_hw *ah,
 				  struct ath9k_channel *chan,