net: remove skb_sender_cpu_clear()

After commit 52bd2d62ce67 ("net: better skb->sender_cpu and skb->napi_id cohabitation")
skb_sender_cpu_clear() becomes empty and can be removed.

Cc: Eric Dumazet <[e-mail]>
Signed-off-by: Cong Wang <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

include/linux/skbuff.h

···
 	to->l4_hash = from->l4_hash;
 };
 
-static inline void skb_sender_cpu_clear(struct sk_buff *skb)
-{
-}
-
 #ifdef NET_SKBUFF_DATA_USES_OFFSET
 static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
 {

net/bridge/br_forward.c

···
 
 	skb_push(skb, ETH_HLEN);
 	br_drop_fake_rtable(skb);
-	skb_sender_cpu_clear(skb);
 
 	if (skb->ip_summed == CHECKSUM_PARTIAL &&
 	    (skb->protocol == htons(ETH_P_8021Q) ||

net/core/filter.c

···
 	}
 
 	skb2->dev = dev;
-	skb_sender_cpu_clear(skb2);
 	return dev_queue_xmit(skb2);
 }
 
···
 	}
 
 	skb->dev = dev;
-	skb_sender_cpu_clear(skb);
 	return dev_queue_xmit(skb);
 }
 

net/core/skbuff.c

···
 	skb->skb_iif = 0;
 	skb->ignore_df = 0;
 	skb_dst_drop(skb);
-	skb_sender_cpu_clear(skb);
 	secpath_reset(skb);
 	nf_reset(skb);
 	nf_reset_trace(skb);

net/ipv4/ip_forward.c

···
 	if (unlikely(opt->optlen))
 		ip_forward_options(skb);
 
-	skb_sender_cpu_clear(skb);
 	return dst_output(net, sk, skb);
 }
 

net/ipv6/ip6_output.c

···
 static inline int ip6_forward_finish(struct net *net, struct sock *sk,
 				     struct sk_buff *skb)
 {
-	skb_sender_cpu_clear(skb);
 	return dst_output(net, sk, skb);
 }
 

net/netfilter/ipvs/ip_vs_xmit.c

···
 	if (ret == NF_ACCEPT) {
 		nf_reset(skb);
 		skb_forward_csum(skb);
-		if (!skb->sk)
-			skb_sender_cpu_clear(skb);
 	}
 	return ret;
 }
···
 
 	if (!local) {
 		skb_forward_csum(skb);
-		if (!skb->sk)
-			skb_sender_cpu_clear(skb);
 		NF_HOOK(pf, NF_INET_LOCAL_OUT, cp->ipvs->net, NULL, skb,
 			NULL, skb_dst(skb)->dev, dst_output);
 	} else
···
 	if (!local) {
 		ip_vs_drop_early_demux_sk(skb);
 		skb_forward_csum(skb);
-		if (!skb->sk)
-			skb_sender_cpu_clear(skb);
 		NF_HOOK(pf, NF_INET_LOCAL_OUT, cp->ipvs->net, NULL, skb,
 			NULL, skb_dst(skb)->dev, dst_output);
 	} else

net/netfilter/nf_dup_netdev.c

···
 		skb_push(skb, skb->mac_len);
 
 	skb->dev = dev;
-	skb_sender_cpu_clear(skb);
 	dev_queue_xmit(skb);
 }
 EXPORT_SYMBOL_GPL(nf_dup_netdev_egress);

net/sched/act_mirred.c

···
 
 	skb2->skb_iif = skb->dev->ifindex;
 	skb2->dev = dev;
-	skb_sender_cpu_clear(skb2);
 	err = dev_queue_xmit(skb2);
 
 	if (err) {