cipso: cleanup cipso_v4_translate() when !CONFIG_NETLABEL

Don't needlessly recompute 'opt[opt_iter + 1]' as we already have it
stored in 'tag_len'.

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/cipso_ipv4.h

@@ -303,7 +303,7 @@ static inline int cipso_v4_validate(const struct sk_buff *skb,
 
 	for (opt_iter = 6; opt_iter < opt_len;) {
 		tag_len = opt[opt_iter + 1];
-		if ((tag_len == 0) || (opt[opt_iter + 1] > (opt_len - opt_iter))) {
+		if ((tag_len == 0) || (tag_len > (opt_len - opt_iter))) {
 			err_offset = opt_iter + 1;
 			goto out;
 		}