Interface names with dashes can cause problems in Ansible since dashes
are replaced with underscores when referencing facts. In the baremetal
role we reference the fact for api_interface without replacing dashes
with underscores. This may result in host entries being omitted from
/etc/hosts.
This change fixes the issue.
Change-Id: I667adc7d8a7dbd20dbfa293f389e02355f8275bb
Related-Bug: #1927357