ipv4: icmp: use icmp_sk_exit()

Simply use icmp_sk_exit() when inet_ctl_sock_create() fail in icmp_sk_init().
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/icmp.c

@@ -1245,9 +1245,7 @@ static int __net_init icmp_sk_init(struct net *net)
 	return 0;
 
 fail:
-	for_each_possible_cpu(i)
-		inet_ctl_sock_destroy(*per_cpu_ptr(net->ipv4.icmp_sk, i));
-	free_percpu(net->ipv4.icmp_sk);
+	icmp_sk_exit(net);
 	return err;
 }