ath9k_hw: Disable Walsh spatial spreading for 2 chains

The Walsh bit is disabled for regulatory consideration.

FCC limit for walsh enable is lower than that for walsh disable. So
disabling walsh bit will not limit tx power/affect tx power even in
cases where we are not FCC limited (most client cards). If the tx
power is not FCC limited, then enabling/disabling walsh bit will
not affect Avg. EVM/overall performance in any visible manner.

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index 88468a0..33edb56 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -482,7 +482,7 @@
 		(REG_READ(ah, AR_PHY_GEN_CTRL) & AR_PHY_GC_ENABLE_DAC_FIFO);
 
 	/* Enable 11n HT, 20 MHz */
-	phymode = AR_PHY_GC_HT_EN | AR_PHY_GC_SINGLE_HT_LTF1 | AR_PHY_GC_WALSH |
+	phymode = AR_PHY_GC_HT_EN | AR_PHY_GC_SINGLE_HT_LTF1 |
 		  AR_PHY_GC_SHORT_GI_40 | enableDacFifo;
 
 	/* Configure baseband for dynamic 20/40 operation */