mac80211: simplify roc check in idle calculation

There's no need to start iterating the list only to break on the
first item, just use !list_empty() and also simplify the whole
conditional into a single expression.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/iface.c

@@ -101,9 +101,8 @@ static u32 __ieee80211_idle_on(struct ieee80211_local *local)
 static u32 __ieee80211_recalc_idle(struct ieee80211_local *local,
 				   bool force_active)
 {
-	bool working = false, scanning, active;
+	bool working, scanning, active;
 	unsigned int led_trig_start = 0, led_trig_stop = 0;
-	struct ieee80211_roc_work *roc;
 
 	lockdep_assert_held(&local->mtx);
 
@@ -111,12 +110,8 @@ static u32 __ieee80211_recalc_idle(struct ieee80211_local *local,
 		 !list_empty(&local->chanctx_list) ||
 		 local->monitors;
 
-	if (!local->ops->remain_on_channel) {
-		list_for_each_entry(roc, &local->roc_list, list) {
-			working = true;
-			break;
-		}
-	}
+	working = !local->ops->remain_on_channel &&
+		  !list_empty(&local->roc_list);
 
 	scanning = test_bit(SCAN_SW_SCANNING, &local->scanning) ||
 		   test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);