netfilter: Add blank lines in callers of netfilter hooks

In code review it was noticed that I had failed to add some blank lines
in places where they are customarily used.  Taking a second look at the
code I have to agree blank lines would be nice so I have added them
here.
Reported-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/xfrm4_output.c

@@ -97,6 +97,7 @@ static int __xfrm4_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 int xfrm4_output(struct sock *sk, struct sk_buff *skb)
 {
 	struct net *net = dev_net(skb_dst(skb)->dev);
+
 	return NF_HOOK_COND(NFPROTO_IPV4, NF_INET_POST_ROUTING,
 			    net, sk, skb, NULL, skb_dst(skb)->dev,
 			    __xfrm4_output,

net/ipv6/ip6_output.c

@@ -136,6 +136,7 @@ int ip6_output(struct sock *sk, struct sk_buff *skb)
 	struct net_device *dev = skb_dst(skb)->dev;
 	struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 	struct net *net = dev_net(dev);
+
 	if (unlikely(idev->cnf.disable_ipv6)) {
 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
 		kfree_skb(skb);

net/ipv6/xfrm6_output.c

@@ -169,6 +169,7 @@ static int __xfrm6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 int xfrm6_output(struct sock *sk, struct sk_buff *skb)
 {
 	struct net *net = dev_net(skb_dst(skb)->dev);
+
 	return NF_HOOK_COND(NFPROTO_IPV6, NF_INET_POST_ROUTING,
 			    net, sk, skb,  NULL, skb_dst(skb)->dev,
 			    __xfrm6_output,

net/xfrm/xfrm_output.c

@@ -132,6 +132,7 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
 int xfrm_output_resume(struct sk_buff *skb, int err)
 {
 	struct net *net = xs_net(skb_dst(skb)->xfrm);
+
 	while (likely((err = xfrm_output_one(skb, err)) == 0)) {
 		nf_reset(skb);