glib glib-utils gdbus-codegen: only warn on doc failures

This is an intentional deviation from Gentoo upstream because
in CrOS document generation is flaky so we convert the errors
into warnings.

BUG=b/183876649,b/183876470
TEST=Presubmit
RELEASE_NOTE=None

Change-Id: If3c0f5dec436e556921d31117d6ae3f2e0bfbc67
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/overlays/chromiumos-overlay/+/3129460
Reviewed-by: Manoj Gupta <manojgupta@chromium.org>
Commit-Queue: Manoj Gupta <manojgupta@chromium.org>
Tested-by: Manoj Gupta <manojgupta@chromium.org>
Reviewed-on: https://cos-review.googlesource.com/c/third_party/overlays/chromiumos-overlay/+/22672
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
5 files changed