net/enic: enable GENEVE offload via VNIC configuration

net/enic: enable GENEVE offload via VNIC configuration

The admin-configured vNIC settings (i.e. via CIMC or UCSM) now include
Geneve offload. Use that setting to decide whether to enable or
disable Geneve offload and remove the devarg 'geneve-opt'.

Also, the firmware now allows the driver to change the Geneve port
number. So extend udp_tunnel_port_{add,del} to accept Geneve port, in
addition to VXLAN.

Fixes: 93fb21fdbe23 ("net/enic: enable overlay offload for VXLAN and GENEVE")
Cc: stable@dpdk.org
Signed-off-by: John Daley <johndale@cisco.com>
Reviewed-by: Hyong Youb Kim <hyonkim@cisco.com>