net/mlx5e: Support TSO and TX checksum offloads for IP-in-IP

tunnels

Add TX offloads support for IP-in-IP tunneled packets by reporting
the needed netdev features.

Signed-off-by: Marina Varshaver <marinav@mellanox.com>
Signed-off-by: Avihu Hagag <avihuh@mellanox.com>
Reviewed-by: Aya Levin <ayal@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>