!3745 【OLK-6.6】Support SMT control on arm64

Merge Pull Request from: @liujie-248683921 
 
The core CPU control framework supports runtime SMT control which is not yet supported on arm64. Besides the general vulnerabilities concerns we want this runtime control on our arm64 server for:

- better single CPU performance in some cases
- saving overall power consumption

This patchset implements it in the following aspects:

- implements the basic support in arch_topology driver
- support retrieve SMT thread number on OF based system
- support retrieve SMT thread number on ACPI based system
- select HOTPLUG_SMT for arm64

https://gitee.com/openeuler/kernel/issues/I8TAPW

Tests has been done on our real ACPI based arm64 server and on ACPI/OF based QEMU VMs. 
 
Link:https://gitee.com/openeuler/kernel/pulls/3745

 

Reviewed-by: Zhang Jianhua <chris.zjh@huawei.com>
Reviewed-by: Weilong Chen <chenweilong@huawei.com>
Reviewed-by: Liu Chao <liuchao173@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>