powerpc/idle: Don't corrupt back chain when going idle
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 v5.4.156 by commit 8e25a62e8dab7bb09da337354ed1be5df61f83a0, it was introduced in version v5.4.156 by commit 80bbb0bc3a0288442f7fe6fc514f4ee1cb06ccb7. For more details please see the references link.