tests/qapi-schema: Make test-qapi.py print arrays

The next few commits mess with array types, and having the changes
exposed in output of test-qapi.py will be useful.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190301154051.23317-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[Rationale added to commit message]
2 files changed