linux/hardened: condition DEBUG_CREDENTIALS to whenOlder than 6.6
Removed on 6.6.8
commit 207f135d819344c03333246f784f6666e652e081
Author: Jens Axboe <axboe@kernel.dk>
Date: Fri Dec 15 13:40:57 2023 -0700
cred: get rid of CONFIG_DEBUG_CREDENTIALS
commit ae1914174a63a558113e80d24ccac2773f9f7b2b upstream.
This code is rarely (never?) enabled by distros, and it hasn't caught
anything in decades. Let's kill off this legacy debug code.
https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.6.8
(cherry picked from commit f3568456727d90cd0f612899f027175105c53327)