char: xillybus: fix a refcount leak in cleanup_dev()
This is an automated ID intended to aid in discovery of potential security vulnerabilities. The actual impact and attack plausibility have not yet been proven. This ID is fixed in Linux Kernel version v5.18.4 by commit e277b95acdab84cd5d2f8d537a37aef6d21e988b. For more details please see the references link.