We can't trap SIGKILL
Disable SIGPIPE and errxit when cleaning up. We always want to try our best to cleanup.

This fixes a case where the status messages (msg, msg_error) during cleanup
would receive EPIPE and cause a recursive failure. This would end up
not unmounting anything or cleaning up jails.
Cleanly exit on SIGPIPE
blah
Backout [d155258190]