arm64: KVM: split GICv2 world switch from hyp code

Move the GICv2 world switch code into its own file, and add the
necessary indirection to the arm64 switch code.

Also introduce a new type field to the vgic_params structure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 1348e74..7867b9a 100644
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -1568,6 +1568,9 @@
 
 	on_each_cpu(vgic_init_maintenance_interrupt, NULL, 1);
 
+	/* Callback into for arch code for setup */
+	vgic_arch_setup(vgic);
+
 	return 0;
 
 out_free_irq: