mac80211: remove a redundant check

ieee80211_is_nullfunc() implies ieee80211_is_data()

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 7948079..f570801 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -1067,8 +1067,7 @@
 void ieee80211_sta_tx_notify(struct ieee80211_sub_if_data *sdata,
 			     struct ieee80211_hdr *hdr)
 {
-	if (!ieee80211_is_data(hdr->frame_control) &&
-	    !ieee80211_is_nullfunc(hdr->frame_control))
+	if (!ieee80211_is_data(hdr->frame_control))
 	    return;
 
 	ieee80211_sta_reset_conn_monitor(sdata);