[reproducer] Pass extra_variable_files to deployment args for PreMetal

PreMetal provisions hosts from the main branch, generating
reproducer-variables.yml with base scenario vars. During the actual
Zuul job, overwrite_zuul_vars.yml only merges zuul_vars.yaml into
reproducer-variables.yml, ignoring extra_variable_files entirely.

This means any scenario override passed via extra_variable_files
is silently lost on the controller. The base values from PreMetal
provisioning win, causing jobs to run the wrong test plan.

Iteratively append each extra_variable_files entry as `-e @<file>`
to cifmw_deploy_architecture_args and cifmw_post_deploy_args before
the zuul_vars.yaml merge, preserving the correct precedence:
base < extra_variable_files < zuul_vars.

Author: srac0

roles/reproducer/tasks/premetal.yml

@@ -30,6 +30,19 @@
   loop_control:
     loop_var: secret_file
 
+- name: Pass extra variable files to deployment scripts
+  when: extra_variable_files is defined
+  ansible.builtin.set_fact:
+    cifmw_deploy_architecture_args: >
+      {{ cifmw_deploy_architecture_args | default('') }}
+      -e @{{ extra_variable_file }}
+    cifmw_post_deploy_args: >
+      {{ cifmw_post_deploy_args | default('') }}
+      -e @{{ extra_variable_file }}
+  loop: "{{ extra_variable_files }}"
+  loop_control:
+    loop_var: extra_variable_file
+
 - name: Print final cifmw_deploy_architecture_args
   ansible.builtin.debug:
     msg: >