[XFRM]: Do not flush all bundles on SA insert.

Instead, simply set all potentially aliasing existing xfrm_state
objects to have the current generation counter value.

This will make routes get relooked up the next time an existing
route mentioning these aliased xfrm_state objects gets used,
via xfrm_dst_check().

Signed-off-by: David S. Miller <davem@davemloft.net>

net/xfrm/xfrm_policy.c

@@ -1478,16 +1478,6 @@ int xfrm_flush_bundles(void)
 	return 0;
 }
 
-static int always_true(struct dst_entry *dst)
-{
-	return 1;
-}
-
-void xfrm_flush_all_bundles(void)
-{
-	xfrm_prune_bundles(always_true);
-}
-
 void xfrm_init_pmtu(struct dst_entry *dst)
 {
 	do {