ath9k_hw: simplify revision checks for AR9285

Since AR9285 v1.0 and v1.1 were never sold (and the initvals removed),
its revision checks can be simplified similar to AR9280

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index 7b6f66b..0014048 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -455,7 +455,7 @@
 		rfilt |= ATH9K_RX_FILTER_BEACON;
 
 	if ((AR_SREV_9280_20_OR_LATER(sc->sc_ah) ||
-	    AR_SREV_9285_10_OR_LATER(sc->sc_ah)) &&
+	    AR_SREV_9285_12_OR_LATER(sc->sc_ah)) &&
 	    (sc->sc_ah->opmode == NL80211_IFTYPE_AP) &&
 	    (sc->rx.rxfilter & FIF_PSPOLL))
 		rfilt |= ATH9K_RX_FILTER_PSPOLL;