More missing `Hint Mode`s.
This MR adds all the Hint Mode
s from @Blaisorblade's iris!696 (merged) to std++ with the exception of the controversial one for Equiv
(see https://github.com/coq/coq/issues/14441), but including the ones for Set
s.
Iris requires a one line fix, see iris!696 (comment 68611)
examples, reloc, iron, actris, and lambdarust all compile without changes.
I think we're still missing more Hint Mode
s, but I am not sure what's a proper way to detect them.