The previous interface was pretty bad, and required the caller to get some
implementation details correct that it really shouldn't need to (e.g.
loader_conf_files handling) and pass in an empty table for it to use.
The new and much improved interface, readConf, is much less of a hack;
hiding these implementation details and just doing the right thing.
config.lua will now use it to process /boot/defaults/loader.conf and the
subsequent loader_conf_files from there, and read-conf will also use it.
This improvement submitted by Olivier (cited below), loader_conf_files
handling from the original patch was changed to just clobber it before
processing and not bother restoring it after the fact following r360505
where it's now guaranteed to evade the loader environment.
PR: 244640
Submitted by: Olivier Certner (olivier freebsd free fr>