tests: Restore check-qdict unit test

Commit ea3af47d accidentally dropped check-qdict from the list of unit
tests.  Put it back.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1477386565-26225-1-git-send-email-armbru@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>