[IPSEC]: Fix bogus usage of u64 on input sequence number

Al Viro spotted a bogus use of u64 on the input sequence number which
is big-endian.  This patch fixes it by giving the input sequence number
its own member in the xfrm_skb_cb structure.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index fc69036..569d377 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -62,7 +62,7 @@
 		}
 
 		if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
-			XFRM_SKB_CB(skb)->seq = ++x->replay.oseq;
+			XFRM_SKB_CB(skb)->seq.output = ++x->replay.oseq;
 			if (unlikely(x->replay.oseq == 0)) {
 				XFRM_INC_STATS(LINUX_MIB_XFRMOUTSTATESEQERROR);
 				x->replay.oseq--;