xfrm: Const'ify ptr args to xfrm_policy_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 f766e5f..2de0bc2 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -1956,7 +1956,7 @@
  * Otherwise "-2 - errored_index" is returned.
  */
 static inline int
-xfrm_policy_ok(struct xfrm_tmpl *tmpl, struct sec_path *sp, int start,
+xfrm_policy_ok(const struct xfrm_tmpl *tmpl, const struct sec_path *sp, int start,
 	       unsigned short family)
 {
 	int idx = start;