KVM: arm64: Add kvm_arch::dvm_cpumask and dvm_lock

virt inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I62Q2L


CVE: NA

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Introduce dvm_cpumask and dvm_lock in struct kvm_arch. dvm_cpumask will
store the union of all vcpus' cpus_ptr and will be used for the TLBI
broadcast range. dvm_lock ensures a exclusive manipulation of dvm_cpumask.

In vcpu_load, we should decide whether to perform the subsequent update
operation by checking whether dvm_cpumask has changed.

Signed-off-by: Quan Zhou <zhouquan65@huawei.com>
Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>
Reviewed-by: Nianyao Tang <tangnianyao@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>