KVM: x86: Use LVT_TIMER instead of an open coded literal

Use LVT_TIMER instead of the literal '0' to clean up the apic_lvt_mask
lookup when emulating handling writes to APIC_LVTT.

No functional change intended.

Signed-off-by: Liam Ni <zhiguangni01@gmail.com>
[sean: manually regenerate patch (whitespace damaged), massage changelog]
Signed-off-by: Sean Christopherson <seanjc@google.com>

Author: Liam Ni

arch/x86/kvm/lapic.c

@@ -2357,7 +2357,7 @@ static int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
 	case APIC_LVTT:
 		if (!kvm_apic_sw_enabled(apic))
 			val |= APIC_LVT_MASKED;
-		val &= (apic_lvt_mask[0] | apic->lapic_timer.timer_mode_mask);
+		val &= (apic_lvt_mask[LVT_TIMER] | apic->lapic_timer.timer_mode_mask);
 		kvm_lapic_set_reg(apic, APIC_LVTT, val);
 		apic_update_lvtt(apic);
 		break;