flow_dissector: add mpls support (v2)

Add support for parsing MPLS flows to the flow dissector in preparation for
adding MPLS match support to cls_flower.

Signed-off-by: Benjamin LaHaise <benjamin.lahaise@netronome.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Eric Dumazet <jhs@mojatatu.com>
Cc: Hadar Hen Zion <hadarh@mellanox.com>
Cc: Gao Feng <fgao@ikuai8.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/mpls.h b/include/linux/mpls.h
index 9999145..384fb22 100644
--- a/include/linux/mpls.h
+++ b/include/linux/mpls.h
@@ -3,4 +3,9 @@
 
 #include <uapi/linux/mpls.h>
 
+#define MPLS_TTL_MASK		(MPLS_LS_TTL_MASK >> MPLS_LS_TTL_SHIFT)
+#define MPLS_BOS_MASK		(MPLS_LS_S_MASK >> MPLS_LS_S_SHIFT)
+#define MPLS_TC_MASK		(MPLS_LS_TC_MASK >> MPLS_LS_TC_SHIFT)
+#define MPLS_LABEL_MASK		(MPLS_LS_LABEL_MASK >> MPLS_LS_LABEL_SHIFT)
+
 #endif  /* _LINUX_MPLS_H */