KVM: ARM: vgic: revisit implementation of irqchip_in_kernel

So far, irqchip_in_kernel() was implemented by testing the value of
vctrl_base, which worked fine with GICv2.

With GICv3, this field is useless, as we're using system registers
instead of a emmory mapped interface. To solve this, add a boolean
flag indicating if the we're using a vgic or not.

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index d8d52a9..f6b9fec 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -117,6 +117,7 @@
 struct vgic_dist {
 #ifdef CONFIG_KVM_ARM_VGIC
 	spinlock_t		lock;
+	bool			in_kernel;
 	bool			ready;
 
 	/* Virtual control interface mapping */
@@ -212,7 +213,7 @@
 bool vgic_handle_mmio(struct kvm_vcpu *vcpu, struct kvm_run *run,
 		      struct kvm_exit_mmio *mmio);
 
-#define irqchip_in_kernel(k)	(!!((k)->arch.vgic.vctrl_base))
+#define irqchip_in_kernel(k)	(!!((k)->arch.vgic.in_kernel))
 #define vgic_initialized(k)	((k)->arch.vgic.ready)
 
 int vgic_v2_probe(struct device_node *vgic_node,