x86/cpu: Create Hygon Dhyana architecture support file

x86/cpu: Create Hygon Dhyana architecture support file

Add x86 architecture support for a new processor: Hygon Dhyana Family
18h. To make Hygon initialization flow more clear, carve out code from
amd.c into a separate file hygon.c, and remove unnecessary code for
Hygon Dhyana.

To identify Hygon Dhyana CPU, add a new vendor type X86_VENDOR_HYGON
and vendor ID "HygonGenuine" for system recognition, and fit the new
x86 vendor lookup mechanism.

Hygon can fully use the function early_init_amd(), so make this common
function non-static and direct call it from Hygon code.

Add a separate hygon_get_topology(), which calculate phys_proc_id from
AcpiId[6](see reference [1]).

Reference:
[1] https://git.kernel.org/tip/e0ceeae708cebf22c990c3d703a4ca187dc837f5

Signed-off-by: Pu Wen <puwen@hygon.cn>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
[Rebase over 0cd074144cb "x86/cpu: Renumber X86_VENDOR_* to form a bitmap" and
             64933920c9b "x86/cpu: Drop cpu_devs[] and $VENDOR_init_cpu() hooks"]
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>