Bug 1658249

Description of problem:
Importing a VM from OVA that has imported before corrupts the disk of the first imported VM. Same with importing a VM from OVA on a HE where the original VM still exists will render the disk of the original VM "illegal".

Version-Release number of selected component (if applicable):
ovirt-engine-setup-4.2.5.2-0.1.el7ev.noarch

How reproducible:
Always

Steps to Reproduce:
1. Export a VM to OVA:
   webUI -> Compute -> Virtual Machines -> <vm> -> Menu -> Export as OVA
2. On a different HE, Compute -> Virtual Machines -> Menu -> Import
   Source: Virtual Appliance (OVA)
   and follow the steps to import the VM
3. Rename the imported VM
4. Repeat step 2

Actual results:
The second import fails, the task displays a RED "X" with
"Importing VM host1 to Cluster Default" 
The disk of the original (first imported VM) under
Compute -> Virtual Machines -> <vm> -> Disks
shows: "Status: Illegal"


Expected results:
Import to succeed resulting in a new VM with new UUID and new disk.


Additional info:
It seems that importing a VM from OVA will keep its UUID but its disk will get
a new UUID (seen from the API) resulting in the first imported VM having a
failed imported disk which is corrupt.

First imported or original VM data:
https://rhvm.home.lan//ovirt-engine/api/vms/dfc25f65-cc4e-44b5-9356-79e70354261e/diskattachments
<disk href="/ovirt-engine/api/disks/05339fff-775b-403b-8c6b-05b4b450c7e9" id="05339fff-775b-403b-8c6b-05b4b450c7e9"/>

Second imported VM has a different UUID for the disk:
<disk href="/ovirt-engine/api/disks/90c9db9d-5625-47a8-bd3a-e78b4abeb1ac" id="90c9db9d-5625-47a8-bd3a-e78b4abeb1ac"/>

However the UUID of the VM remained the same!