46795cf2e2
QOM API learning curve is quite hard, in particular when devices inherit from abstract parent. To be more explicit about when a device class change the parent hooks, add few helpers hoping a device class_init() will be easier to understand. Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-Id: <20180114020412.26160-3-f4bug@amsat.org> Reviewed-by: Laurent Vivier <laurent@vivier.eu> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>