xfrm: Const'ify ptr args to xfrm_state_ok.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 3a4221a..f766e5f 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1933,7 +1933,7 @@
  */
 
 static inline int
-xfrm_state_ok(struct xfrm_tmpl *tmpl, struct xfrm_state *x,
+xfrm_state_ok(const struct xfrm_tmpl *tmpl, const struct xfrm_state *x,
 	      unsigned short family)
 {
 	if (xfrm_state_kern(x))