KVM: nVMX: vmx_complete_nested_posted_interrupt() can't fail

(cherry picked from commit 6342c50a)

vmx_complete_nested_posted_interrupt() can't fail, let's turn it into
a void function.
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
[jwang: port to 4.4]
Signed-off-by: Jack Wang <jinpu.wang@profitbricks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/x86/kvm/vmx.c

@@ -4512,7 +4512,7 @@ static int vmx_cpu_uses_apicv(struct kvm_vcpu *vcpu)
 	return enable_apicv && lapic_in_kernel(vcpu);
 }
 
-static int vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu)
+static void vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_vmx *vmx = to_vmx(vcpu);
 	int max_irr;
@@ -4523,13 +4523,13 @@ static int vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu)
 	    vmx->nested.pi_pending) {
 		vmx->nested.pi_pending = false;
 		if (!pi_test_and_clear_on(vmx->nested.pi_desc))
-			return 0;
+			return;
 
 		max_irr = find_last_bit(
 			(unsigned long *)vmx->nested.pi_desc->pir, 256);
 
 		if (max_irr == 256)
-			return 0;
+			return;
 
 		vapic_page = kmap(vmx->nested.virtual_apic_page);
 		__kvm_apic_update_irr(vmx->nested.pi_desc->pir, vapic_page);
@@ -4542,7 +4542,6 @@ static int vmx_complete_nested_posted_interrupt(struct kvm_vcpu *vcpu)
 			vmcs_write16(GUEST_INTR_STATUS, status);
 		}
 	}
-	return 0;
 }
 
 static inline bool kvm_vcpu_trigger_posted_interrupt(struct kvm_vcpu *vcpu)
@@ -10155,7 +10154,8 @@ static int vmx_check_nested_events(struct kvm_vcpu *vcpu, bool external_intr)
 		return 0;
 	}
 
-	return vmx_complete_nested_posted_interrupt(vcpu);
+	vmx_complete_nested_posted_interrupt(vcpu);
+	return 0;
 }
 
 static u32 vmx_get_preemption_timer_value(struct kvm_vcpu *vcpu)