ipv6: Fix fragment id assignment on LE arches.

Recent commit:
0508c07f
Author: Vlad Yasevich <vyasevich@gmail.com>
Date:   Tue Feb 3 16:36:15 2015 -0500

    ipv6: Select fragment id during UFO segmentation if not set.

Introduced a bug on LE in how ipv6 fragment id is assigned.
This was cought by nightly sparce check:

Resolve the following sparce error:
 net/ipv6/output_core.c:57:38: sparse: incorrect type in assignment
 (different base types)
   net/ipv6/output_core.c:57:38:    expected restricted __be32
[usertype] ip6_frag_id
   net/ipv6/output_core.c:57:38:    got unsigned int [unsigned]
[assigned] [usertype] id

Fixes: 0508c07f (ipv6: Select fragment id during UFO segmentation if not set.)
Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/output_core.c

@@ -54,7 +54,7 @@ void ipv6_proxy_select_ident(struct sk_buff *skb)
 
 	id = __ipv6_select_ident(ip6_proxy_idents_hashrnd,
 				 &addrs[1], &addrs[0]);
-	skb_shinfo(skb)->ip6_frag_id = id;
+	skb_shinfo(skb)->ip6_frag_id = htonl(id);
 }
 EXPORT_SYMBOL_GPL(ipv6_proxy_select_ident);