KVM: arm/arm64: vgic-its: Make attribute accessors static

Fix sparse warnings:

arch/arm64/kvm/../../../virt/kvm/arm/vgic/vgic-its.c:1732:5: warning:
symbol 'vgic_its_has_attr_regs' was not declared. Should it be static?
arch/arm64/kvm/../../../virt/kvm/arm/vgic/vgic-its.c:1753:5: warning:
symbol 'vgic_its_attr_regs_access' was not declared. Should it be static?

Signed-off-by: YueHaibing <[e-mail]>
[maz: fixed subject]
Signed-off-by: Marc Zyngier <[e-mail]>

virt/kvm/arm/vgic/vgic-its.c

···
 	kfree(its);
 }
 
-int vgic_its_has_attr_regs(struct kvm_device *dev,
-			   struct kvm_device_attr *attr)
+static int vgic_its_has_attr_regs(struct kvm_device *dev,
+				  struct kvm_device_attr *attr)
 {
 	const struct vgic_register_region *region;
 	gpa_t offset = attr->attr;
···
 	return 0;
 }
 
-int vgic_its_attr_regs_access(struct kvm_device *dev,
-			      struct kvm_device_attr *attr,
-			      u64 *reg, bool is_write)
+static int vgic_its_attr_regs_access(struct kvm_device *dev,
+				     struct kvm_device_attr *attr,
+				     u64 *reg, bool is_write)
 {
 	const struct vgic_register_region *region;
 	struct vgic_its *its;