qmp: Use ObjectProperty.type if present

The dynamic value is more informative in the case of link property,
otherwise it is the same.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170714021509.23681-5-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/qmp.c b/qmp.c
index e6b68fe..2cd40c3 100644
--- a/qmp.c
+++ b/qmp.c
@@ -486,7 +486,8 @@
 
             info = g_malloc0(sizeof(*info));
             info->name = g_strdup(prop->name);
-            info->type = g_strdup(prop->info->name);
+            info->type = default_type ? g_strdup(default_type)
+                                      : g_strdup(prop->info->name);
             info->has_description = !!prop->info->description;
             info->description = g_strdup(prop->info->description);
             return info;