Before this commit, `make test` stopped after running the TLS tests if there
was a failure.
Have `run-test-suites.pl` take care of looking in all the directories, so
that the last line of output from `make test` is an accurate report of all
the test suites, not just the test suites from the last run of
`run-test-suites.pl`.
Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>