net: mpls: Add support for netconf

Add netconf support to MPLS. Allows userpsace to learn and be notified
of changes to 'input' enable setting per interface.

Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mpls/internal.h b/net/mpls/internal.h
index d972430..76360d8 100644
--- a/net/mpls/internal.h
+++ b/net/mpls/internal.h
@@ -16,7 +16,7 @@ struct mpls_pcpu_stats {
 
 struct mpls_dev {
 	int				input_enabled;
-
+	struct net_device		*dev;
 	struct mpls_pcpu_stats __percpu	*stats;
 
 	struct ctl_table_header		*sysctl;