Enforce similar cgroup replacement pattern across OSes, fix lint naming

Signed-off-by: Derek Nola <derek.nola@suse.com>

roles/raspberrypi/tasks/prereq/Archlinux.yml

@@ -1,6 +1,6 @@
 ---
 - name: Check for boot configuration files
-  ansible.builtin.stat:
+  ansible.builtin.stat: # noqa var-naming[no-role-prefix]
     path: "{{ item }}"
   loop:
     - /boot/boot.txt
@@ -9,25 +9,12 @@
 
 - name: Set boot_file fact
   ansible.builtin.set_fact:
-    rpi_boot_file: "{{ (boot_files.results | selectattr('stat.exists') | map(attribute='item') | list | first) | default('') }}"
+    raspberrypi_boot_file: "{{ (boot_files.results | selectattr('stat.exists') | map(attribute='item') | list | first) | default('') }}"
 
-- name: Enable cgroup via boot commandline (boot.txt)
+# Arch ARM64 boots via /boot/boot.txt (UBoot), /boot/cmdline.txt only exists on legacy 32-bit systems
+- name: Enable cgroup via boot commandline
   ansible.builtin.replace:
-    path: /boot/boot.txt
-    regexp: '^(setenv bootargs console=ttyS1,115200 console=tty0 root=PARTUUID=\${uuid} rw rootwait smsc95xx.macaddr="\${usbethaddr}"(?!.*\b{{ cgroup_item }}\b).*)$'
-    replace: '\1 {{ cgroup_item }}'
-  with_items:
-    - "cgroup_enable=cpuset"
-    - "cgroup_memory=1"
-    - "cgroup_enable=memory"
-  loop_control:
-    loop_var: cgroup_item
-  when: rpi_boot_file == '/boot/boot.txt'
-  notify: Regenerate bootloader image
-
-- name: Enable cgroup via boot commandline (cmdline.txt)
-  ansible.builtin.replace:
-    path: /boot/cmdline.txt
+    path: "{{ raspberrypi_boot_file }}"
     regexp: '^([\w](?!.*\b{{ cgroup_item }}\b).*)$'
     replace: '\1 {{ cgroup_item }}'
   with_items:
@@ -36,5 +23,4 @@
     - "cgroup_enable=memory"
   loop_control:
     loop_var: cgroup_item
-  when: rpi_boot_file == '/boot/cmdline.txt'
-  notify: Reboot Pi
+  notify: "{{ (raspberrypi_boot_file == '/boot/boot.txt') | ternary('Regenerate bootloader image', 'Reboot Pi') }}"