bridge: remove dev_put() in add_del_if()

add_del_if() is called with RTNL, we can use __dev_get_by_index()
instead of [dev_get_by_index() + dev_put()]
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/bridge/br_ioctl.c

@@ -81,6 +81,7 @@ static int get_fdb_entries(struct net_bridge *br, void __user *userbuf,
 	return num;
 }
 
+/* called with RTNL */
 static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
 {
 	struct net_device *dev;
@@ -89,7 +90,7 @@ static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
 	if (!capable(CAP_NET_ADMIN))
 		return -EPERM;
 
-	dev = dev_get_by_index(dev_net(br->dev), ifindex);
+	dev = __dev_get_by_index(dev_net(br->dev), ifindex);
 	if (dev == NULL)
 		return -EINVAL;
 
@@ -98,7 +99,6 @@ static int add_del_if(struct net_bridge *br, int ifindex, int isadd)
 	else
 		ret = br_del_if(br, dev);
 
-	dev_put(dev);
 	return ret;
 }