ovn: don't explicitly set vlan-limit=0

ovn-controller does it automatically since 21.09.0 [1].

This patch also gracefully handles a case where external_ids passed as
variable are empty, if it ever happens.

ovn-org/ovn@7e2c892

roles/edpm_ovn/defaults/main.yml

@@ -85,5 +85,4 @@ edpm_ovn_ovs_external_ids:
   rundir: "/var/run/openvswitch"
 
 # Set openvswitch other_config.
-edpm_ovn_ovs_other_config:
-  vlan-limit: 0
+edpm_ovn_ovs_other_config: {}

roles/edpm_ovn/meta/argument_specs.yml

@@ -127,8 +127,7 @@ argument_specs:
         description: Sets external_id data from provided variables using Jinja templating
         type: dict
       edpm_ovn_ovs_other_config:
-        default:
-          vlan-limit: 0
+        default: {}
         description: Openvswitch other_config
         type: dict
       edpm_ovn_protocol:

roles/edpm_ovn/tasks/configure.yml

@@ -66,13 +66,15 @@
   register: ovs_external_ids
   changed_when: ovs_external_ids.rc == 0
   failed_when: ovs_external_ids.rc != 0
+  when: edpm_ovn_ovs_external_ids | length > 0
 
 - name: Configure OVS other_config
   ansible.builtin.shell: >
     ovs-vsctl set open . {% for key, value in edpm_ovn_ovs_other_config.items() %} other_config:{{ key }}={{ value }} {% endfor %}
   register: ovs_other_config
   changed_when: ovs_other_config.rc == 0
   failed_when: ovs_other_config.rc != 0
+  when: edpm_ovn_ovs_other_config | length > 0
 
 - name: Add OVS Manager
   block: