This commit introduces the MPLSoGRE support (RFC 4023), using ip tunnel
API by simply adding ipgre_tunnel_encap_(add|del)_mpls_ops() and the new
tunnel type TUNNEL_ENCAP_MPLS.
Signed-off-by: NAmine Kherbouche <amine.kherbouche@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>