[PATCH-for-5.2 2/3] gitlab-ci: Add a job to cover the --without-default-devices config

["Philippe Mathieu-Daudé" <philmd@redhat.com>]

We test './configure --without-default-devices' since commit
20885b5b169 (".travis.yml: test that no-default-device builds
do not regress") in Travis-CI.

As we prefer to use GitLab-CI, add the equivalent job there.

One minor difference: the GitLab Ubuntu docker image has the
Xen devel packages installed. As it is automatically selected,
we need to disable it with the --disable-xen option, else the
build fails:

  /usr/bin/ld: libcommon.fa.p/hw_xen_xen-legacy-backend.c.o: in function `xen_be_register_common':
  hw/xen/xen-legacy-backend.c:754: undefined reference to `xen_9pfs_ops'
  /usr/bin/ld: libcommon.fa.p/fsdev_qemu-fsdev.c.o:(.data.rel+0x8): undefined reference to `local_ops'
  /usr/bin/ld: libcommon.fa.p/fsdev_qemu-fsdev.c.o:(.data.rel+0x20): undefined reference to `synth_ops'
  /usr/bin/ld: libcommon.fa.p/fsdev_qemu-fsdev.c.o:(.data.rel+0x38): undefined reference to `proxy_ops'
  collect2: error: ld returned 1 exit status

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 .gitlab-ci.yml | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 3b15ae5c302..6ee098ec53c 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -262,6 +262,17 @@ build-user-plugins:
     MAKE_CHECK_ARGS: check-tcg
   timeout: 1h 30m
 
+build-system-ubuntu-without-default-devices:
+  <<: *native_build_job_definition
+  variables:
+    IMAGE: ubuntu2004
+    CONFIGURE_ARGS: --without-default-devices --disable-user --disable-xen --disable-tools --disable-docs
+    MAKE_CHECK_ARGS: check-build
+  artifacts:
+    expire_in: 2 days
+    paths:
+      - build
+
 build-clang:
   <<: *native_build_job_definition
   variables:
-- 
2.26.2