tty: synclink_gt: Fix null-pointer-dereference in slgt_clean()
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 v5.15.47 by commit 8a95696bdc0e13f8980f05b54a3b9081963d1256. For more details please see the references link.