Commit a25c937f8a ("test: add logging API test") causes the build to
fail in the Chromium OS build environment, because the return value of a
function call marked with the __warn_unused_result__ attribute is ignored.
Fix this.
Fixes: a25c937f8a ("test: add logging API test")
Signed-off-by: Paul Elder <paul.elder@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>