Recently neutron public network type has been changed by default
to flat [0]. It caused ironic-multitenant-network job to failure.
This patch update settings in ironic/settings untill apropriate changes
are merged to project-config and developer documentation.
Reference:
[0] https://review.openstack.org/#/c/346282/
Change-Id: Icd83203f1c61f71c96324c532baabe3a924cf617
a53dae62af