net/mlx5: support ethernet type for tunnels on E-Switch

net/mlx5: support ethernet type for tunnels on E-Switch

This patch add support for inner and outer ethernet types for the
E-Switch Flows with tunnels. Inner and outer ethernet type match
can be specified with ethernet items, vlan items, or implicitly
deduced from IP address items. The tcm_info field in Netlink message
tcm structure is filled always with outer protocol.

Cc: stable@dpdk.org
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
Acked-by: Shahaf Shuler <shahafs@mellanox.com>