arm64/topology: getting preferred sibling's cpumask supported by platform

hulk inclusion
category: performance
bugzilla: https://gitee.com/openeuler/kernel/issues/I5QK5M


CVE: NA

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For some architectures, masking the underlying processor topology
differences can make software unable to identify the cpu distance,
which results in performance fluctuations.

So we provide additional interface for getting preferred sibling's
cpumask supported by platform, this siblings' cpumask indicates those
CPUs which are clustered with relatively short distances, but this
hardly depends on the specific implementation of the specific platform.

Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>