ath9k_htc: add new WMI_REG_RMW_CMDID command

Since usb bus add extra delay on each request, a command
with read + write requests is too expensive. We can dramtically
reduce usb load by moving this command to firmware.

In my tests, this patch will reduce channel scan time
for about 5-10 seconds.

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git a/drivers/net/wireless/ath/ath.h b/drivers/net/wireless/ath/ath.h
index 1eebe2e..7e94810 100644
--- a/drivers/net/wireless/ath/ath.h
+++ b/drivers/net/wireless/ath/ath.h
@@ -131,6 +131,9 @@
 	void (*enable_write_buffer)(void *);
 	void (*write_flush) (void *);
 	u32 (*rmw)(void *, u32 reg_offset, u32 set, u32 clr);
+	void (*enable_rmw_buffer)(void *);
+	void (*rmw_flush) (void *);
+
 };
 
 struct ath_common;