ath9k_hw: set pci_express capability true for AR9480

the AR_SREV register does not seems to indicate whether AR9480 is
pci_express capable or not though the other information like macVersion
etc can be obtained properly. this fix is essential as ASPM won't be intialized
and its related driver functionality ath9k_hw_configpcipowersave won't be
called

Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath9k/hw.c

@@ -284,7 +284,12 @@ static void ath9k_hw_read_revisions(struct ath_hw *ah)
 		ah->hw_version.macVersion =
 			(val & AR_SREV_VERSION2) >> AR_SREV_TYPE2_S;
 		ah->hw_version.macRev = MS(val, AR_SREV_REVISION2);
-		ah->is_pciexpress = (val & AR_SREV_TYPE2_HOST_MODE) ? 0 : 1;
+
+		if (AR_SREV_9480(ah))
+			ah->is_pciexpress = true;
+		else
+			ah->is_pciexpress = (val &
+					     AR_SREV_TYPE2_HOST_MODE) ? 0 : 1;
 	} else {
 		if (!AR_SREV_9100(ah))
 			ah->hw_version.macVersion = MS(val, AR_SREV_VERSION);