- Pass tcf_result into tcf_action_exec()
- Update res->classid and res->class on non-zero
  skb->tc_classid, then reset skb->tc_classid
- Update tcf_action_exec() callers in cls_u32.c
  and cls_fw.c

Based upon a patch by Jamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>