- When we run our trap cleanup handler, echo that we are running this

- When we run our trap cleanup handler, echo that we are running this
  handler to make it more clear why we are 'suddenly' running df,
  umount, and mdconfig.
- Remove trap handler again after we have unconfigured the memory
  device etc.  Before we could end up running the trap handler if a
  later stage failed, which was a bit confusing and not really useful.

MFC after:	2 weeks