xfrm: policy: remove garbage_collect callback

Just call xfrm_garbage_collect_deferred() directly.
This gets rid of a write to afinfo in register/unregister and allows to
constify afinfo later on.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 794148f7..80695a1 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -2733,10 +2733,11 @@ void xfrm_garbage_collect(struct net *net)
 }
 EXPORT_SYMBOL(xfrm_garbage_collect);
 
-static void xfrm_garbage_collect_deferred(struct net *net)
+void xfrm_garbage_collect_deferred(struct net *net)
 {
 	flow_cache_flush_deferred(net);
 }
+EXPORT_SYMBOL(xfrm_garbage_collect_deferred);
 
 static void xfrm_init_pmtu(struct dst_entry *dst)
 {
@@ -2873,8 +2874,6 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 			dst_ops->link_failure = xfrm_link_failure;
 		if (likely(dst_ops->neigh_lookup == NULL))
 			dst_ops->neigh_lookup = xfrm_neigh_lookup;
-		if (likely(afinfo->garbage_collect == NULL))
-			afinfo->garbage_collect = xfrm_garbage_collect_deferred;
 		rcu_assign_pointer(xfrm_policy_afinfo[afinfo->family], afinfo);
 	}
 	spin_unlock(&xfrm_policy_afinfo_lock);
@@ -2901,7 +2900,6 @@ void xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
 	dst_ops->check = NULL;
 	dst_ops->negative_advice = NULL;
 	dst_ops->link_failure = NULL;
-	afinfo->garbage_collect = NULL;
 }
 EXPORT_SYMBOL(xfrm_policy_unregister_afinfo);