ath9k_hw: program OBS register only when MCI is disabled

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/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index a9d328c..4ec496d 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1915,7 +1915,8 @@
 
 	ath9k_hw_set_dma(ah);
 
-	REG_WRITE(ah, AR_OBS, 8);
+	if (!ath9k_hw_mci_is_enabled(ah))
+		REG_WRITE(ah, AR_OBS, 8);
 
 	if (ah->config.rx_intr_mitigation) {
 		REG_RMW_FIELD(ah, AR_RIMT, AR_RIMT_LAST, 500);