qom: allow user-creatable classes to be in modules

There is no real reason to make user-creatable classes different
from other backends in this respect.  This also allows modularized
character devices to be treated by qom-list-properties just like
builtin ones.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qom/object_interfaces.c

@@ -90,7 +90,7 @@ Object *user_creatable_add_type(const char *type, const char *id,
         return NULL;
     }
 
-    klass = object_class_by_name(type);
+    klass = module_object_class_by_name(type);
     if (!klass) {
         error_setg(errp, "invalid object type: %s", type);
         return NULL;

qom/qom-qmp-cmds.c

@@ -186,7 +186,7 @@ ObjectPropertyInfoList *qmp_qom_list_properties(const char *typename,
     ObjectPropertyIterator iter;
     ObjectPropertyInfoList *prop_list = NULL;
 
-    klass = object_class_by_name(typename);
+    klass = module_object_class_by_name(typename);
     if (klass == NULL) {
         error_set(errp, ERROR_CLASS_DEVICE_NOT_FOUND,
                   "Class '%s' not found", typename);