engine: adding base_interface column to vds_interface table

We should accept vlan devices identified by any name (and not only
baseIface.vlanId)
Therefore the baseInterface name cannot longer be determined from the
vlan device name.
If the interface is vlan the columns will contain the base interface
name.

Change-Id: I87ac5121b9e7d3b74f5557336e5d504ef91b7702
Bug-Url: https://bugzilla.redhat.com/1091863
Bug-Url: https://bugzilla.redhat.com/999975
Signed-off-by: Alona Kaplan <alkaplan@redhat.com>