oldland: implement exceptions.

This implements the swi and rfe instructions, control register handling
and support for exceptions.
tests: add push/pop macros for convenience.
tests: add a wrapper for expected testpoints.

Deduplicate a bunch of code in tests.
tests: print testpoint types in a friendly format.
tests: use sim bootrom when running tests.

It's a smaller rom that doesn't touch any registers.
sim: fix bad indentation.
verif: don't print pts number for batch runs.