added default value for system_upgrade_states

tasks/upgrade.yml

@@ -3,6 +3,9 @@
   set_fact:
     doreboot: False 
 
+- debug:
+    var: system_upgrade_states
+
 - block:
    - name: get hostname of migrationhost
      set_fact:
@@ -27,14 +30,13 @@
        create_nullfs: True
        migration_host: "{{ migrationhostip }}"
      when: (not (_container.key in contlist.jails) or _container.value == True) and _container.key != 'host'
-     loop: "{{ system_upgrade_states[migrationhost] | dict2items }}"
+     loop: "{{ system_upgrade_states[migrationhost] | default({}) | dict2items }}"
      loop_control:
        loop_var: _container
   
    - name: set variable that controls the reboot of the host
      set_fact:
        doreboot: "{{ system_upgrade_states[migrationhost].host }}"
-
   when: system_upgrade_states is defined
 
 - block: