scripts/unit-test: Detect problematic valgrind

Instead of permanently blacklisting valgrind from running in our unit
test environment for all powerpc platforms, run a problematic test case
to determine if we can use valgrind or not.

Tested:
    Ran on amd64 and ppc64el to verify that valgrind is still run on the
    currently working amd64 and not on the currently broken ppc64el.

Change-Id: Ie028a5cc9ec9138c78a87f58c70af274adca2c95
Signed-off-by: William A. Kennington III <wak@google.com>
1 file changed