qdev: Fix adding of ptr properties

ptr properties have neither a get/set or a print/parse which means that when
they're added they aren't treated as static or legacy properties.

Just assume properties like this are legacy properties and treat them as such.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/hw/qdev.c b/hw/qdev.c
index 0bcde20..6a8f6bd 100644
--- a/hw/qdev.c
+++ b/hw/qdev.c
@@ -576,9 +576,12 @@
 {
     gchar *name, *type;
 
-    if (!prop->info->print && !prop->info->parse) {
+    /* Register pointer properties as legacy properties */
+    if (!prop->info->print && !prop->info->parse &&
+        (prop->info->set || prop->info->get)) {
         return;
     }
+
     name = g_strdup_printf("legacy-%s", prop->name);
     type = g_strdup_printf("legacy<%s>",
                            prop->info->legacy_name ?: prop->info->name);