fix backtraces with compiled boot-9

fix backtraces with compiled boot-9

* module/ice-9/boot-9.scm (default-pre-unwind-handler): Since we were
  tail-called by pre-unwind-handler-dispatch, we can't use
  pre-unwind-handler-dispatch as a narrowing argument. Instead just
  narrow by one frame.
  (pre-unwind-handler-dispatch): Deprecate.
  (error-catching-loop): Remove crack comment and code, and just use
  default-pre-unwind-handler as our pre-unwind handler.

* module/ice-9/stack-catch.scm (stack-catch):
* module/system/repl/repl.scm (call-with-backtrace): Use
  default-pre-unwind-handler directly.