Fix logic for installing a routing file

In Ansible, a "string"|bool jinja2 filter does not result to a true
value as presented below:

~$ ansible localhost -e foo="string" -m debug -a "msg={{foo|bool}}"
localhost | SUCCESS => {
    "msg": false
}

Only a "true" string results in a boolean True value

~$ ansible localhost -e foo="true" -m debug -a "msg={{foo|bool}}"
localhost | SUCCESS => {
    "msg": true
}

as such, the routing files where never installed for the RedHat
distributions. We fix this logic by simply leaving this variable
undefined for the distributions who don't need it.

Change-Id: I0af0ad47487365ad593c5550d2c7e05f650e7174

tasks/container_create.yml

@@ -288,8 +288,8 @@
     group: "root"
     mode: "0644"
   when:
-    - lxc_container_route_interface | bool
-    - lxc_container_default_route_interfaces | bool
+    - lxc_container_route_interface is defined
+    - lxc_container_default_route_interfaces is defined
     - item.value.static_routes is defined
   with_dict: "{{ container_networks | default({}) }}"
   delegate_to: "{{ physical_host }}"

vars/ubuntu-16.04.yml

@@ -18,10 +18,6 @@
 #   Ansible iterator type is `with_dict`.
 lxc_container_interface: debian-interface.cfg.j2
 
-# Notice this is already resolved in the debian interface file
-lxc_container_route_interface: false
-lxc_container_default_route_interfaces: false
-
 # Note this is a used in an iterable and requires the <item.value.interface> variable
 lxc_container_interface_target: "/etc/network/interfaces.d/{{ item.value.interface }}.cfg"