Drop custom_iso_enabled and log defaults

roles/environment/tasks/main.yml

@@ -17,7 +17,7 @@
 
     - name: Abort if the host is not booted from the Arch install media
       when:
-        - not custom_iso_enabled
+        - not (custom_iso | bool)
         - not environment_archiso_stat.stat.exists
       ansible.builtin.fail:
         msg: This host is not booted from the Arch install media!
@@ -88,14 +88,14 @@
     - name: Prepare installer environment
       block:
         - name: Speed-up Bootstrap process
-          when: not custom_iso_enabled
+          when: not (custom_iso | bool)
           ansible.builtin.lineinfile:
             path: /etc/pacman.conf
             regexp: ^#ParallelDownloads =
             line: ParallelDownloads = 20
 
         - name: Wait for pacman lock to be released
-          when: not custom_iso_enabled
+          when: not (custom_iso | bool)
           ansible.builtin.wait_for:
             path: /var/lib/pacman/db.lck
             state: absent
@@ -104,7 +104,7 @@
 
         - name: Setup Pacman
           when:
-            - not custom_iso_enabled
+            - not (custom_iso | bool)
             - "'os' not in item or os in item.os"
           community.general.pacman:
             update_cache: true