[NETFILTER]: Rename skb_ip_make_writable() to skb_make_writable()

There is nothing IPv4-specific in it.  In fact, it was already used by
IPv6, too...  Upcoming nfnetlink_queue code will use it for any kind
of packet.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/netfilter/ipt_ECN.c b/net/ipv4/netfilter/ipt_ECN.c
index f63a9bc..a131969 100644
--- a/net/ipv4/netfilter/ipt_ECN.c
+++ b/net/ipv4/netfilter/ipt_ECN.c
@@ -31,7 +31,7 @@
 	    != (einfo->ip_ect & IPT_ECN_IP_MASK)) {
 		u_int16_t diffs[2];
 
-		if (!skb_ip_make_writable(pskb, sizeof(struct iphdr)))
+		if (!skb_make_writable(pskb, sizeof(struct iphdr)))
 			return 0;
 
 		diffs[0] = htons((*pskb)->nh.iph->tos) ^ 0xFFFF;
@@ -66,7 +66,7 @@
 	     tcph->cwr == einfo->proto.tcp.cwr)))
 		return 1;
 
-	if (!skb_ip_make_writable(pskb, (*pskb)->nh.iph->ihl*4+sizeof(*tcph)))
+	if (!skb_make_writable(pskb, (*pskb)->nh.iph->ihl*4+sizeof(*tcph)))
 		return 0;
 	tcph = (void *)(*pskb)->nh.iph + (*pskb)->nh.iph->ihl*4;