Allow to pass default interface values to tempest

In case any of those are set in ironic, test that resets interfaces
might fail.

Closes-issue: https://mirantis.jira.com/browse/PRODX-9563
Change-Id: I6f07e25644a92ccac169f84f7c79696d21b58e76
(cherry picked from commit 675c7c0109c8d83f1d8de9b3d28b0e93dd900595)
2 files changed