ath9k: disable RIFS search for AR91xx based chips

While ath9k does not support RIFS yet, the ability to receive RIFS
frames is currently enabled for most chipsets in the initvals.
This is causing baseband related issues on AR9160 and AR9130 based
chipsets, which can lock up under certain conditions.

This patch fixes these issues by overriding the initvals, effectively
disabling RIFS for all affected chipsets.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Acked-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/phy.h b/drivers/net/wireless/ath/ath9k/phy.h
index 31de27d..0999a49 100644
--- a/drivers/net/wireless/ath/ath9k/phy.h
+++ b/drivers/net/wireless/ath/ath9k/phy.h
@@ -384,6 +384,9 @@
 
 #define AR_PHY_HEAVY_CLIP_ENABLE         0x99E0
 
+#define AR_PHY_HEAVY_CLIP_FACTOR_RIFS    0x99EC
+#define AR_PHY_RIFS_INIT_DELAY         0x03ff0000
+
 #define AR_PHY_M_SLEEP      0x99f0
 #define AR_PHY_REFCLKDLY    0x99f4
 #define AR_PHY_REFCLKPD     0x99f8