KVM: ARM: VGIC: Optimize the vGIC vgic_update_irq_pending function.

When vgic_update_irq_pending with level-sensitive false, it is need to
deactivates an interrupt, and, it can go to out directly.
Here return a false value, because it will be not need to kick.
Signed-off-by: wanghaibin <wanghaibin.wang@huawei.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

virt/kvm/arm/vgic.c

@@ -1646,6 +1646,9 @@ static bool vgic_update_irq_pending(struct kvm *kvm, int cpuid,
 		} else {
 			vgic_dist_irq_clear_pending(vcpu, irq_num);
 		}
+
+		ret = false;
+		goto out;
 	}
 
 	enabled = vgic_irq_is_enabled(vcpu, irq_num);