kvm: x86: check kvm_apic_sw_enabled() is enough

On delivering irq to apic, we iterate on vcpu and do the check like
this:

    kvm_apic_present(vcpu)
    kvm_lapic_enabled(vpu)
        kvm_apic_present(vcpu) && kvm_apic_sw_enabled(vcpu->arch.apic)

Since we have already checked kvm_apic_present(), it is reasonable to
replace kvm_lapic_enabled() with kvm_apic_sw_enabled().
Signed-off-by: NWei Yang <richardw.yang@linux.intel.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

arch/x86/kvm/irq_comm.c

@@ -86,7 +86,7 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 			if (r < 0)
 				r = 0;
 			r += kvm_apic_set_irq(vcpu, irq, dest_map);
-		} else if (kvm_lapic_enabled(vcpu)) {
+		} else if (kvm_apic_sw_enabled(vcpu->arch.apic)) {
 			if (!kvm_vector_hashing_enabled()) {
 				if (!lowest)
 					lowest = vcpu;