misc/57706: atf_tc_expect_fail is confused by rump panic

[campbell+netbsd%mumble.net@localhost]

>Number:         57706
>Category:       misc
>Synopsis:       atf_tc_expect_fail is confused by rump panic
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    misc-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Nov 19 01:10:00 +0000 2023
>Originator:     Taylor R Campbell
>Release:        current
>Organization:
The RumpBSD Atffoundation
>Environment:
>Description:
I put atf_tc_expect_fail("...") in a test that uses rump and panics on KASSERT failure, but atf still considers the test to be a(n unexpected) failure, not an expected failure.
>How-To-Repeat:
atf_tc_expect_fail("panic");
call panic() in rump;
>Fix:
Yes, please!