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]
diff --git a/tests/qapi-schema/test-qapi.py b/tests/qapi-schema/test-qapi.py
index d592854..d21fca0 100644
--- a/tests/qapi-schema/test-qapi.py
+++ b/tests/qapi-schema/test-qapi.py
@@ -32,6 +32,12 @@
             self._print_if(m.ifcond, indent=8)
         self._print_if(ifcond)
 
+    def visit_array_type(self, name, info, ifcond, element_type):
+        if not info:
+            return              # suppress built-in arrays
+        print('array %s %s' % (name, element_type.name))
+        self._print_if(ifcond)
+
     def visit_object_type(self, name, info, ifcond, base, members, variants):
         print('object %s' % name)
         if base: