mac80211: fix a typo in ieee80211_handle_filtered_frame comment

fix a typo in ieee80211_handle_filtered_frame comment

Signed-off-by: Yi Zhu <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 915afad..5c87645 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -1313,7 +1313,7 @@
 	/*
 	 * Clear the TX filter mask for this STA when sending the next
 	 * packet. If the STA went to power save mode, this will happen
-	 * happen when it wakes up for the next time.
+	 * when it wakes up for the next time.
 	 */
 	sta->flags |= WLAN_STA_CLEAR_PS_FILT;