KVM: PPC: Support irq routing and irqfd for in-kernel MPIC

Now that all the irq routing and irqfd pieces are generic, we can expose
real irqchip support to all of KVM's internal helpers.

This allows us to use irqfd with the in-kernel MPIC.

Signed-off-by: Alexander Graf <agraf@suse.de>

arch/powerpc/kvm/irq.h

@@ -0,0 +1,17 @@
+#ifndef __IRQ_H
+#define __IRQ_H
+
+#include <linux/kvm_host.h>
+
+static inline int irqchip_in_kernel(struct kvm *kvm)
+{
+	int ret = 0;
+
+#ifdef CONFIG_KVM_MPIC
+	ret = ret || (kvm->arch.mpic != NULL);
+#endif
+	smp_rmb();
+	return ret;
+}
+
+#endif