Based on the idea that we shouldn't have all-new library and utility going
into base that need WARNS=1...
- Decent amount of constification
- Lots of parentheses
- Minor other nits
For the moment, this is a primitive nvlist dump of what we get back from
be_get_bootenv_props as a proof-of-concept and to make sure that we're
getting back the kind of information we want to see from list.