Datapath: Change in openvswitch kernel module to support MPLS label depth of 3 in...

Datapath: Change in openvswitch kernel module to support MPLS label depth of 3 in ingress direction.

Upstream commit:
    commit fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3
    Author: Martin Varghese <martin.varghese@nokia.com>
    Date:   Mon Nov 4 07:27:44 2019 +0530

    Change in Openvswitch to support MPLS label depth of 3 in ingress
    direction

    The openvswitch was supporting a MPLS label depth of 1 in the
    ingress direction though the userspace OVS supports a max depth
    of 3 labels.This change enables openvswitch module to support a
    max depth of 3 labels in the ingress.

    Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
    Acked-by: Pravin B Shelar <pshelar@ovn.org>
    Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Greg Rose <gvrose8192@gmail.com>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: Martin Varghese <martin.varghese@nokia.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>