Make PHYSICAL_INTERFACE_MAPPINGS variable...

instead of just one provuider interface.
it should contain something like:
physnet2:eth1,physnet3:eth2

roles/neutron-controller/tasks/main.yml

@@ -30,7 +30,7 @@
         -e "NOVA_PLACEMENT_PASSWORD={{ secrets['NOVA_PLACEMENT_PASSWORD'] }}"
         -e "NOVA_PLACEMENT_USER=placement"
         -e "OS_PASSWORD={{ secrets['OS_PASSWORD'] }}"
-        -e "PROVIDER_INTERFACE_NAME={{ provider_interface_name }}"
+        -e "PHYSICAL_INTERFACE_MAPPINGS={{ physical_interface_mappings }}"
         -e "RABBIT_PASSWORD={{ secrets['RABBIT_PASSWORD'] }}"
         -e "RABBIT_USER=openstack"
   tags: env