qom/container: remove .instance_size initializer from container_info

You can omit .instance_size if it is the same as that of the parent.

    .class_size = sizeof(ObjectClass)

... is omitted here, so removing .instance_size is more consistent.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Message-Id: <20200513033600.2709646-1-masahiroy@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

qom/container.c

@@ -16,7 +16,6 @@
 
 static const TypeInfo container_info = {
     .name          = "container",
-    .instance_size = sizeof(Object),
     .parent        = TYPE_OBJECT,
 };