KVM: arm64: vgic-v3: Take cpu_if pointer directly instead of vcpu

If we move the used_lrs field to the version-specific cpu interface
structure, the following functions only operate on the struct
vgic_v3_cpu_if and not the full vcpu:

  __vgic_v3_save_state
  __vgic_v3_restore_state
  __vgic_v3_activate_traps
  __vgic_v3_deactivate_traps
  __vgic_v3_save_aprs
  __vgic_v3_restore_aprs

This is going to be very useful for nested virt, so move the used_lrs
field and change the prototypes and implementations of these functions to
take the cpu_if parameter directly.

No functional change.

Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index 69f4164..a8d8fdc 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -274,6 +274,8 @@ struct vgic_v2_cpu_if {
 	u32		vgic_vmcr;
 	u32		vgic_apr;
 	u32		vgic_lr[VGIC_V2_MAX_LRS];
+
+	unsigned int used_lrs;
 };
 
 struct vgic_v3_cpu_if {
@@ -291,6 +293,8 @@ struct vgic_v3_cpu_if {
 	 * linking the Linux IRQ subsystem and the ITS together.
 	 */
 	struct its_vpe	its_vpe;
+
+	unsigned int used_lrs;
 };
 
 struct vgic_cpu {
@@ -300,7 +304,6 @@ struct vgic_cpu {
 		struct vgic_v3_cpu_if	vgic_v3;
 	};
 
-	unsigned int used_lrs;
 	struct vgic_irq private_irqs[VGIC_NR_PRIVATE_IRQS];
 
 	raw_spinlock_t ap_list_lock;	/* Protects the ap_list */