Squashfs: fix handling and sanity checking of xattr_ids count
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 v5.15.93 by commit 997bed0f3cde78a3e639d624985bf4a95cf767e6, it was introduced in version v5.11 by commit 506220d2ba21791314af569211ffd8870b8208fa. For more details please see the references link.