qom: Drop object_property_del_child()'s unused parameter @errp

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-4-armbru@redhat.com>
diff --git a/qom/object.c b/qom/object.c
index 07762cc..3d65658 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -614,7 +614,7 @@
     g_hash_table_unref(obj->properties);
 }
 
-static void object_property_del_child(Object *obj, Object *child, Error **errp)
+static void object_property_del_child(Object *obj, Object *child)
 {
     ObjectProperty *prop;
     GHashTableIter iter;
@@ -644,7 +644,7 @@
 void object_unparent(Object *obj)
 {
     if (obj->parent) {
-        object_property_del_child(obj->parent, obj, NULL);
+        object_property_del_child(obj->parent, obj);
     }
 }