KVM: nVMX: Expose load IA32_PERF_GLOBAL_CTRL VM-{Entry,Exit} control

The "load IA32_PERF_GLOBAL_CTRL" bit for VM-entry and VM-exit should
only be exposed to the guest if IA32_PERF_GLOBAL_CTRL is a valid MSR.
Create a new helper to allow pmu_refresh() to update the VM-Entry and
VM-Exit controls to ensure PMU values are initialized when performing
the is_valid_msr() check.

Suggested-by: Jim Mattson <jmattson@google.com>
Co-developed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com>
Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx/nested.h

@@ -22,6 +22,7 @@ int vmx_set_vmx_msr(struct kvm_vcpu *vcpu, u32 msr_index, u64 data);
 int vmx_get_vmx_msr(struct nested_vmx_msrs *msrs, u32 msr_index, u64 *pdata);
 int get_vmx_mem_address(struct kvm_vcpu *vcpu, unsigned long exit_qualification,
 			u32 vmx_instruction_info, bool wr, int len, gva_t *ret);
+void nested_vmx_pmu_entry_exit_ctls_update(struct kvm_vcpu *vcpu);
 
 static inline struct vmcs12 *get_vmcs12(struct kvm_vcpu *vcpu)
 {