revlog: drop some more error aliases (API)
These should be lightly used and I doubt that will be any
strong objections to removing the aliases.
Note that some uses of ProgrammingError in this file use
translated messages. I'm pretty sure that's a bug. But the
linters don't complain, so meh.
Differential Revision: https://phab.mercurial-scm.org/D4652