ath9k: fix MGMT packets when using TKIP

Prevent 8 bytes from being truncated from MGMT packets
when using TKIP.

Signed-off-by: Bill Jordan <bjordan@rajant.com>
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 a9d8f96b..ad5f9bd 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -824,7 +824,8 @@
 	is_mc = !!is_multicast_ether_addr(hdr->addr1);
 	is_valid_tkip = rx_stats->rs_keyix != ATH9K_RXKEYIX_INVALID &&
 		test_bit(rx_stats->rs_keyix, common->tkip_keymap);
-	strip_mic = is_valid_tkip && !(rx_stats->rs_status &
+	strip_mic = is_valid_tkip && ieee80211_is_data(fc) &&
+		!(rx_stats->rs_status &
 		(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_CRC | ATH9K_RXERR_MIC));
 
 	if (!rx_stats->rs_datalen)