mac802154: move interface del handling in iface

This patch moves and rename the mac802154_del_iface function into
iface.c and rename the function to ieee802154_if_remove which is a similar
naming convention like mac80211.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

net/mac802154/iface.c

@@ -443,3 +443,15 @@ void mac802154_monitor_setup(struct net_device *dev)
 
 	sdata->promisuous_mode = true;
 }
+
+void ieee802154_if_remove(struct ieee802154_sub_if_data *sdata)
+{
+	ASSERT_RTNL();
+
+	mutex_lock(&sdata->local->iflist_mtx);
+	list_del_rcu(&sdata->list);
+	mutex_unlock(&sdata->local->iflist_mtx);
+
+	synchronize_rcu();
+	unregister_netdevice(sdata->dev);
+}