x86/cpu/centaur: Add Centaur family >=7 CPUs initialization support

Add Centaur family >=7 CPUs specific initialization support.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/1599562666-31351-3-git-send-email-TonyWWang-oc@zhaoxin.com