[retro-gtk/build-doc] ci: Fix reference Meson args

[Adrien Plazas <aplazas src gnome org>]

commit e24a5b817269689c04c40b759e755412f9fc33d2
Author: Adrien Plazas <kekun plazas laposte net>
Date:   Sun Apr 12 10:22:28 2020 +0200

    ci: Fix reference Meson args

 .gitlab-ci.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index fc23b95..0dbf5af 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -77,7 +77,7 @@ flatpak:reference:
     MANIFEST_PATH: "flatpak/org.gnome.Retro.Reference.json"
     FLATPAK_MODULE: "retro-gtk"
     FLATPAK_BUILD_DIR: "app"
-    MESON_ARGS: "build-doc=true"
+    MESON_ARGS: "-Dbuild-doc=true"
   script:
     - flatpak-builder --stop-at=${FLATPAK_MODULE} ${FLATPAK_BUILD_DIR} ${MANIFEST_PATH}
     - flatpak build ${FLATPAK_BUILD_DIR} meson --prefix=/app ${MESON_ARGS} _build