xfrm: Remove unused xfrm_state from xfrm_state_check_space

The xfrm_state argument is unused in this function, so remove it.
Also the name xfrm_state_check_space does not really match what this
function does. It actually checks if we have enough head and tailroom
on the skb. So we rename the function to xfrm_skb_check_space.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 47bacd8..95a338c 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -21,7 +21,7 @@
 
 static int xfrm_output2(struct sk_buff *skb);
 
-static int xfrm_state_check_space(struct xfrm_state *x, struct sk_buff *skb)
+static int xfrm_skb_check_space(struct sk_buff *skb)
 {
 	struct dst_entry *dst = skb_dst(skb);
 	int nhead = dst->header_len + LL_RESERVED_SPACE(dst->dev)
@@ -48,7 +48,7 @@
 		goto resume;
 
 	do {
-		err = xfrm_state_check_space(x, skb);
+		err = xfrm_skb_check_space(skb);
 		if (err) {
 			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
 			goto error_nolock;