[2/2] x86/cpu/amd: Add a Zenbleed fix

[2/2] x86/cpu/amd: Add a Zenbleed fix

Origin: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit?id=ed9b87010aa84c157096f98c322491e9af8e8f07
Bug-Debian-Security: https://security-tracker.debian.org/tracker/CVE-2023-20593

Upstream commit: 522b1d69219d8f083173819fde04f994aa051a98

Add a fix for the Zen2 VZEROUPPER data corruption bug where under
certain circumstances executing VZEROUPPER can cause register
corruption or leak data.

The optimal fix is through microcode but in the case the proper
microcode revision has not been applied, enable a fallback fix using
a chicken bit.

Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Gbp-Pq: Topic bugfix/x86
Gbp-Pq: Name x86-cpu-amd-Add-a-Zenbleed-fix.patch