tty: ttybuffer: Fix the softlockup issue in flushto_ldisc
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 v5.4.162 by commit d491c84df5c469dd9621863b6a770b3428137063. For more details please see the references link.