This includes a workaround to a known dnsmasq >= 2.81 issue that
results in unanswered DHCP requests from instances as documented in the
following Neutron bug:
dnsmasq >= 2.81 not responding to DHCP requests with current q-dhcp configs
https://bugs.launchpad.net/neutron/+bug/1896945
For the time being we will attempt to downgrade to 2.80 to avoid this.
Related-Bug: #1896945
Change-Id: I3a760c43956221424926bd9dad0ebe9b28ae2b52