Description of problem:
GET for /api/storagedomains/{storagedomain:id}/vms/ returns vms entities without disks' link.

The link is returned only when accessing the {vm:id} object. This doesn't correspond with the behaviour for other collections (/api/vms/ or /api/templates/) where all the links elements are returned per entity.

Version-Release number of selected component (if applicable):
rhevm-3.4.2-0.1.el6ev.noarch

How reproducible:
100%

Steps to Reproduce:
1. Export a few vm's with disks
2. rest-api call for GET /api/storagedomains/{storagedomain:id}/vms/

Actual results:
list of vm are returned but without the disks' link (is there for /api/storagedomains/{storagedomain:id}/vms/{vm:id})

Expected results:
for each vm entity there's a link to the vm disks' collection

Additional info:
Related: https://bugzilla.redhat.com/show_bug.cgi?id=1117747

Adding a new bug since BZ1117747 was a regression.