mlxsw: spectrum_router: Add support for nexthop objects

Register a listener to the nexthop notification chain and parse notified
nexthop objects into the existing mlxsw nexthop data structures.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.h

@@ -58,6 +58,7 @@ struct mlxsw_sp_router {
 	struct list_head nexthop_neighs_list;
 	struct list_head ipip_list;
 	bool aborted;
+	struct notifier_block nexthop_nb;
 	struct notifier_block fib_nb;
 	struct notifier_block netevent_nb;
 	struct notifier_block inetaddr_nb;