Add zuul gate variable

This PS adds zuul gate variable args.chdir to the jobs where it has been
missed. This variable helps to control relative path to the source code
folder in cases when  playbooks have been inherited.

Change-Id: Iea56ea4d00b9449c129afb34f4f91952fcc015c4

tools/gate/playbooks/docker-image-build.yaml

@@ -63,7 +63,7 @@
       when: not publish
       block:
         - make:
-            chdir: "{{ zuul.project.src_dir }}"
+            chdir: "{{ zuul.project.src_dir }}/{{ args.chdir }}"
             target: "build"
             params:
               DISTRO_SUFFIX: "{{ distro_suffix }}"
@@ -90,7 +90,7 @@
             password: "{{ quay_credentials.password }}"
             registry_url: "https://quay.io/api/v1/"
         - make:
-            chdir: "{{ zuul.project.src_dir }}"
+            chdir: "{{ zuul.project.src_dir }}/{{ args.chdir }}"
             target: "build"
             params:
               COMMIT: "{{ zuul.newrev | default('') }}"

tools/gate/playbooks/make-functional-tests.yaml

@@ -16,7 +16,7 @@
     - name: Execute the make target for unit testing
       block:
         - make:
-            chdir: "{{ zuul.project.src_dir }}"
+            chdir: "{{ zuul.project.src_dir }}/{{ args.chdir }}"
             target: unit_tests
           register: result
           failed_when: result.failed
@@ -26,7 +26,7 @@
     - name: Execute the make target for features testing
       block:
         - make:
-            chdir: "{{ zuul.project.src_dir }}"
+            chdir: "{{ zuul.project.src_dir }}/{{ args.chdir }}"
             target: feature_tests
           register: result
           failed_when: result.failed

tools/gate/playbooks/zuul-linter.yaml

@@ -15,6 +15,6 @@
     - name: Execute a Whitespace Linter check
       command: git grep -E -l " +$"
       args:
-        chdir: "{{ zuul.project.src_dir }}"
+        chdir: "{{ zuul.project.src_dir }}/{{ args.chdir }}"
       register: result
       failed_when: result.stdout != ""

zuul.d/base.yaml

@@ -148,7 +148,8 @@
           commit: false
         static:
           - latest
-
+      args:
+        chdir: ../porthole
 
 - job:
     name: airship-porthole-linter
@@ -157,6 +158,9 @@
     run: tools/gate/playbooks/zuul-linter.yaml
     timeout: 300
     nodeset: airship-porthole-focal-single-node
+    vars:
+      args:
+        chdir: ../porthole
 
 - job:
     name: airship-porthole-deploy-functional-tests-ubuntu_focal