bonding: remove unnecessary NULL check in bond_destructor

The free_percpu function also could check whether "rr_tx_counter"
parameter is NULL. Therefore, remove NULL check in bond_destructor.
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_main.c

@@ -5863,8 +5863,7 @@ static void bond_destructor(struct net_device *bond_dev)
 	if (bond->wq)
 		destroy_workqueue(bond->wq);
 
-	if (bond->rr_tx_counter)
-		free_percpu(bond->rr_tx_counter);
+	free_percpu(bond->rr_tx_counter);
 }
 
 void bond_setup(struct net_device *bond_dev)