net: vlan: fix underflow for the real_dev refcnt
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 v5.15.6 by commit f7fc72a508cf115c273a7a29350069def1041890, it was introduced in version v5.15.3 by commit 21032425c36ff85f16e72ca92193a8c401e4acd5. For more details please see the references link.