fix(cleanup,config): xen tmp cleanup, tpm2 fallback warning, add code comments

roles/cleanup/tasks/xen.yml

@@ -11,7 +11,7 @@
       ansible.builtin.set_fact:
         cleanup_xen_disks: "{{ cleanup_xen_disks | default([]) + [cleanup_xen_disk_cfg] }}"
       vars:
-        device_letter_map: "abcdefghijklmnopqrstuvwxyz"
+        device_letter_map: "{{ disk_letter_map }}"
         device_letter: "{{ device_letter_map[ansible_loop.index0] }}"
         cleanup_xen_disk_cfg: >-
           {{
@@ -58,3 +58,8 @@
           - /tmp/xen-{{ hostname }}.cfg
       register: cleanup_xen_start_result
       changed_when: cleanup_xen_start_result.rc == 0
+
+    - name: Remove temporary Xen configuration file
+      ansible.builtin.file:
+        path: /tmp/xen-{{ hostname }}.cfg
+        state: absent