Created attachment 1584822 [details]
Screenshot showing what nic should be selected to reproduce the issue

Description of problem:

When all following conditions are met, provisioned host won't get a subnet assigned. 

Here are the conditions:
- a discovered host has multiple nics (2 are already enough)
- nic used to discover is the first in the list of available nics when booting the FDI (see attached image)
- when provisioning, no customization is done in the interfaces to assign a subnet manually
- hostgroup doesn't force a subnet, only a domain

Version-Release number of selected component (if applicable):


How reproducible:
always

Steps to Reproduce:
1. Create a hostgroup with NO SUBNET.
2. Create a VM with multiple NICs
3. Boot the VM using the discovery image and ensure you use the first NIC in the list of available nics to boot (see attached image)
4. Use quick submit provisioning with the hostgroup configured in the step 1
5. Check the subnet association of the created host ( Edit -> interfaces -> choose the nic ) and see there is none.

Actual results:
- host has no subnet assigned, actually blocking the provisioning (template rendering failing because there is no subnet).

Expected results:
- host would have the discovered subnet assigned

Additional info:

1. If you do the same steps, but use another nic to discover (the second in the list, for example), the discovered subnet will be assigned

2. In Satellite 6.5 behavior seems to be the same.

3. In Satellite 6.3.5, no such behavior is observed and host always get a subnet.