cfg80211: remove BUG_ON usage

These really can't trigger unless somebody messes up the code,
but don't make debugging it needlessly complicated, WARN and
return instead of BUG_ON().
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/wireless/core.c

@@ -690,7 +690,7 @@ void wiphy_unregister(struct wiphy *wiphy)
 	rtnl_lock();
 	rdev->wiphy.registered = false;
 
-	BUG_ON(!list_empty(&rdev->wdev_list));
+	WARN_ON(!list_empty(&rdev->wdev_list));
 
 	/*
 	 * First remove the hardware from everywhere, this makes

net/wireless/sme.c

@@ -149,7 +149,8 @@ static int cfg80211_conn_do_work(struct wireless_dev *wdev)
 	case CFG80211_CONN_SCAN_AGAIN:
 		return cfg80211_conn_scan(wdev);
 	case CFG80211_CONN_AUTHENTICATE_NEXT:
-		BUG_ON(!rdev->ops->auth);
+		if (WARN_ON(!rdev->ops->auth))
+			return -EOPNOTSUPP;
 		wdev->conn->state = CFG80211_CONN_AUTHENTICATING;
 		return cfg80211_mlme_auth(rdev, wdev->netdev,
 					  params->channel, params->auth_type,
@@ -161,7 +162,8 @@ static int cfg80211_conn_do_work(struct wireless_dev *wdev)
 	case CFG80211_CONN_AUTH_FAILED:
 		return -ENOTCONN;
 	case CFG80211_CONN_ASSOCIATE_NEXT:
-		BUG_ON(!rdev->ops->assoc);
+		if (WARN_ON(!rdev->ops->assoc))
+			return -EOPNOTSUPP;
 		wdev->conn->state = CFG80211_CONN_ASSOCIATING;
 		if (wdev->conn->prev_bssid_valid)
 			req.prev_bssid = wdev->conn->prev_bssid;