The "valgrind" test cases are designed to pick up errors reported when
passt is running under valgrind. But what it actually does is just kill
the passt process, then see if it had a non-zero exit code. That means it
will equally well pick up any other problems which caused passt to exit
with an error status: either something detected within passt or as a result
of passt being killed by an unexpected signal.
The fact that the "valgrind" test is actually responsible for shutting down
the passt process is non-obvious and can lead to problems when selectively
running tests during debugging.
Rename the "valgrind" tests to "shutdown" tests and run it regardless of
whether we're using valgrind or not. This allows us to remove an ugly
speacial case in the passt_in_ns teardown code.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
