In case of VMWare, set promiscous mode for ethernet port connecting to VM

In VMWare, we have a physical-port connecting to vmware-port-group vswitch.
For Layer2 mode to work, this port must be set in promiscous mode. Otherwise,
packets to be bridged will get filtered in MAC.

Add a sub-type for physical-ports. Promiscous mode is set only for interfaces
of type VMWARE.

Change-Id: Ib9ff179af41de77debcc5a5459b531974838a830
Merge "In case of VMWare, set promiscous mode for ethernet port connecting to VM"