kernel/3.10: improve fq_codel hashing for 6in4 6to4 801.ad and IPIP cases

This is a backport of code to improve the quality of fq_codel
hashing for 3.10 for some encapsulated protocols.

Not needed in 3.11 and later.

Patch-by: Dave Taht <dave.taht@bufferbloat.net>
Patchwork: http://patchwork.openwrt.org/patch/4902/
Signed-off-by: Gabor Juhos <juhosg@openwrt.org>

SVN-Revision: 39640

target/linux/generic/patches-3.10/688-net-flow_dissector-add-802.1ad-support.patch

@@ -0,0 +1,24 @@
+From 017879b546ee5f85d13f90236a251d56605c9e86 Mon Sep 17 00:00:00 2001
+From: Eric Dumazet <edumazet@google.com>
+Date: Tue, 6 Aug 2013 04:35:06 -0700
+Subject: [PATCH 5/5] net: flow_dissector: add 802.1ad support
+
+Same behavior than 802.1q : finds the encapsulated protocol and
+skip 32bit header.
+
+Signed-off-by: Eric Dumazet <edumazet@google.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ net/core/flow_dissector.c |    1 +
+ 1 file changed, 1 insertion(+)
+
+--- a/net/core/flow_dissector.c
++++ b/net/core/flow_dissector.c
+@@ -65,6 +65,7 @@ ipv6:
+ 		nhoff += sizeof(struct ipv6hdr);
+ 		break;
+ 	}
++	case __constant_htons(ETH_P_8021AD):
+ 	case __constant_htons(ETH_P_8021Q): {
+ 		const struct vlan_hdr *vlan;
+ 		struct vlan_hdr _vlan;