KVM: vmx: speed up TPR below threshold vmexits

Since we're already in VCPU context, all we have to do here is recompute
the PPR value.  That will in turn generate a KVM_REQ_EVENT if necessary.

Reviewed-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/vmx.c

@@ -6152,7 +6152,7 @@ static int handle_wrmsr(struct kvm_vcpu *vcpu)
 
 static int handle_tpr_below_threshold(struct kvm_vcpu *vcpu)
 {
-	kvm_make_request(KVM_REQ_EVENT, vcpu);
+	kvm_apic_update_ppr(vcpu);
 	return 1;
 }