Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=1573250

Description of problem: I created a host group and associated a compute profile with it to attach Libvirt vms to "foreman" interface

Version-Release number of selected component (if applicable): 6.4

How reproducible: Always

Steps to Reproduce:
1. Create libvirt compute profile. Set attached network interface
2. Associate compute profile with hostgroup
3. Create a vm with hostgroup

Actual results: The compute profile is selected in the UI, but the network interface config is incorrect

Expected results: Network interface config from compute profile is used.

Additional info: attached foreman-debug take after creating host with compute profile, but incorrect network config which led to an error :

Failed to power up a compute locallibvirt (Libvirt) instance kathy-smeenk.lab.eng.rdu2.redhat.com: Call to virDomainCreateWithFlags failed: Cannot get interface MTU on '': No such device