KVM: arm/arm64: Avoid attempting to load timer vgic state without a vgic

The timer optimization patches inadvertendly changed the logic to always
load the timer state as if we have a vgic, even if we don't have a vgic.

Fix this by doing the usual irqchip_in_kernel() check and call the
appropriate load function.
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

virt/kvm/arm/arch_timer.c

@@ -835,6 +835,9 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu)
 no_vgic:
 	preempt_disable();
 	timer->enabled = 1;
+	if (!irqchip_in_kernel(vcpu->kvm))
+		kvm_timer_vcpu_load_user(vcpu);
+	else
 		kvm_timer_vcpu_load_vgic(vcpu);
 	preempt_enable();