afs: Fix dynamic root getattr
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 v5.15.51 by commit 2b2bba96526f25f2eba74ecadb031de2e05a83ce, it was introduced in version v5.15.42 by commit 94bf8bfb009fad247d02f12e4c443411c8445412. For more details please see the references link.