Domain disk change events handler

def _domain_event_disk_change_cb(conn, domain, old_src, new_src, dev, reason, opaque):
    '''
    Domain disk change events handler
    '''
    _salt_send_domain_event(opaque, conn, domain, opaque['event'], {
        'oldSrcPath': old_src,
        'newSrcPath': new_src,
        'dev': dev,
        'reason': _get_libvirt_enum_string('VIR_DOMAIN_EVENT_DISK_', reason)
    })