Some fixes:
- Maintain historical behavior more accurately w.r.t verbose_loading;
verbose_loading strictly prints "${module_name...}" and later "failed!"
or "ok" based on load success
- With or without verbose_loading, dump command_errbuf on load failure.
This usually happens prior to ok/failed if we're verbose_loading
Reviewed by: imp
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D17694
3078173c8d