Disable VLAN 0 tagging for none VLAN traffic

Disable VLAN 0 tagging for none VLAN traffic

Orabug: 14406424
Cisco enic driver on UCS blades tags a None VLAN traffic with VLAN 0, this causes VMs
that do not have the kernel patch " VLAN 0 should be treated as no vlan tag" to drop all
receive traffic as these VMs do not know how to deal with the VLAN 0 tag.
This is also a problem for older VMs that can not take the mentioned patch.

This fix disables the enic driver from tagging a None VLAN traffic with VLAN 0.This
fix is controlled by a driver parameters " disable_vlan0". the default value is disable_vlan0=1
which to disable the driver from tagging traffic with VLAN 0. To revert to original behavior
add "options enic disable_vlan0=0" to /etc/modprobe.con

Signed-off-by: Adnan Misherfi <adnan.misherfi@oracle.com>