arm64: fix extra cpucaps setup problem

hulk inclusion
category: bugfix
bugzilla: 186460, https://gitee.com/src-openeuler/kernel/issues/I53MHA


CVE: CVE-2022-23960

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When introducing a new cpucaps macro ARM64_SPECTRE_BHB, ARM64_NCAPS was
not able to modified easily due to KABI consistency. Here introduce
a workaround to properly setup ARM64_SPECTRE_BHB beyond ARM64_NCAPS
range.

Fixes: def2df57 ("KVM: arm64: Add templates for BHB mitigation sequences")
Signed-off-by: Chen Jiahao <chenjiahao16@huawei.com>
Reviewed-by: Zhang Jianhua <chris.zjh@huawei.com>
Reviewed-by: Liao Chang <liaochang1@huawei.com>
Signed-off-by: Yongqiang Liu <liuyongqiang13@huawei.com>