KVM: SVM: Clean up handling of LBR virtualization enabled

Clean up the enable_lbrv computation in svm_update_lbrv() to consolidate
the logic for computing enable_lbrv into a single statement, and to remove
the coding style violations (lack of curly braces on nested if).

No functional change intended.

Link: https://lore.kernel.org/r/20230607203519.1570167-3-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

arch/x86/kvm/svm/svm.c

@@ -994,15 +994,10 @@ static struct vmcb *svm_get_lbr_vmcb(struct vcpu_svm *svm)
 void svm_update_lbrv(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
-
-	bool enable_lbrv = svm_get_lbr_vmcb(svm)->save.dbgctl & DEBUGCTLMSR_LBR;
-
-	bool current_enable_lbrv = !!(svm->vmcb->control.virt_ext &
-				      LBR_CTL_ENABLE_MASK);
-
-	if (unlikely(is_guest_mode(vcpu) && svm->lbrv_enabled))
-		if (unlikely(svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK))
-			enable_lbrv = true;
+	bool current_enable_lbrv = svm->vmcb->control.virt_ext & LBR_CTL_ENABLE_MASK;
+	bool enable_lbrv = (svm_get_lbr_vmcb(svm)->save.dbgctl & DEBUGCTLMSR_LBR) ||
+			   (is_guest_mode(vcpu) && svm->lbrv_enabled &&
+			    (svm->nested.ctl.virt_ext & LBR_CTL_ENABLE_MASK));
 
 	if (enable_lbrv == current_enable_lbrv)
 		return;