kernel: Add errata patching for AMD "Zenbleed".

Part of #18525.

Change-Id: I6b5d73f6634d122dba13ad9544f340358ddef113
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6767
Reviewed-by: Jérôme Duval <jerome.duval@gmail.com>
Tested-by: Commit checker robot <no-reply+buildbot@haiku-os.org>

x86: identify Hygon vendor

it's a Zen-based CPU: rely on AMD support code.

Change-Id: Ia980a42457575bf8d1130d813310a285bf137691
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3217
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

kernel/x86_64: Add errata patching.

The patched errata are only the AMD ones FreeBSD patches
(it seems there are no Intel errata that can be patched
this way, they are all in microcode updates ... or can't
be patched in the CPU at all.)

This also seems to be roughly the point in the boot that
FreeBSD patches these, too, despite how "critical" some
of them seem.

Change-Id: I9065f8d025332418a21c2cdf39afd7d29405edcc
Reviewed-on: https://review.haiku-os.org/c/haiku/+/1740
Reviewed-by: Jessica Hamilton <jessica.l.hamilton@gmail.com>