gitlab-ci: Extract OpenSBI job rules to reusable section

All jobs depending on 'docker-opensbi' job must use at most all
the rules that triggers it. The simplest way to ensure that
is to always use the same rules. Extract all the rules to a
reusable section, and include this section (with the 'extends'
keyword) in both 'docker-opensbi' and 'build-opensbi' jobs.

The problem was introduced in commit c6fc0fc ("gitlab-ci.yml:
Add jobs to build OpenSBI firmware binaries"), but was revealed in
commit 91e9c47 ("docker: OpenSBI build job depends on OpenSBI
container").

This fix is similar to the one used with the EDK2 firmware job in
commit ac0595c ("gitlab-ci: Extract EDK2 job rules to reusable
section").

Reported-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Willian Rampazzo <willianr@redhat.com>
Message-Id: <20210720164829.3949558-1-philmd@redhat.com>
Message-Id: <20210720232703.10650-30-alex.bennee@linaro.org>

.gitlab-ci.d/opensbi.yml

@@ -1,10 +1,23 @@
-docker-opensbi:
- stage: containers
- rules: # Only run this job when the Dockerfile is modified
+# All jobs needing docker-opensbi must use the same rules it uses.
+.opensbi_job_rules:
+ rules: # Only run this job when ...
  - changes:
+   # this file is modified
    - .gitlab-ci.d/opensbi.yml
+   # or the Dockerfile is modified
    - .gitlab-ci.d/opensbi/Dockerfile
    when: always
+ - changes: # or roms/opensbi/ is modified (submodule updated)
+   - roms/opensbi/*
+   when: always
+ - if: '$CI_COMMIT_REF_NAME =~ /^opensbi/' # or the branch/tag starts with 'opensbi'
+   when: always
+ - if: '$CI_COMMIT_MESSAGE =~ /opensbi/i' # or last commit description contains 'OpenSBI'
+   when: always
+
+docker-opensbi:
+ extends: .opensbi_job_rules
+ stage: containers
  image: docker:19.03.1
  services:
  - docker:19.03.1-dind
@@ -24,16 +37,9 @@ docker-opensbi:
  - docker push $IMAGE_TAG
 
 build-opensbi:
+ extends: .opensbi_job_rules
  stage: build
  needs: ['docker-opensbi']
- rules: # Only run this job when ...
- - changes: # ... roms/opensbi/ is modified (submodule updated)
-   - roms/opensbi/*
-   when: always
- - if: '$CI_COMMIT_REF_NAME =~ /^opensbi/' # or the branch/tag starts with 'opensbi'
-   when: always
- - if: '$CI_COMMIT_MESSAGE =~ /opensbi/i' # or last commit description contains 'OpenSBI'
-   when: always
  artifacts:
    paths: # 'artifacts.zip' will contains the following files:
    - pc-bios/opensbi-riscv32-generic-fw_dynamic.bin