KVM: x86: Move kvm_x86_ops.vcpu_after_set_cpuid() into kvm_vcpu_after_set_cpuid()

kvm_x86_ops.vcpu_after_set_cpuid() is used to update vmx/svm specific
vcpu settings based on updated CPUID settings. So it's supposed to be
called after CPUIDs are updated, i.e., kvm_update_cpuid_runtime().

Currently, kvm_update_cpuid_runtime() only updates CPUID bits of OSXSAVE,
APIC, OSPKE, MWAIT, KVM_FEATURE_PV_UNHALT and CPUID(0xD,0).ebx and
CPUID(0xD, 1).ebx. None of them is consumed by vmx/svm's
update_vcpu_after_set_cpuid(). So there is no dependency between them.

Move kvm_x86_ops.vcpu_after_set_cpuid() into kvm_vcpu_after_set_cpuid() is
obviously more reasonable.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Message-Id: <20200709043426.92712-6-xiaoyao.li@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>