KVM: Future-proof device assignment ABI

Reserve some space so we can add more data.
Signed-off-by: Avi Kivity <avi@qumranet.com>

include/linux/kvm.h

@@ -489,6 +489,9 @@ struct kvm_assigned_pci_dev {
 	__u32 busnr;
 	__u32 devfn;
 	__u32 flags;
+	union {
+		__u32 reserved[12];
+	};
 };
 
 struct kvm_assigned_irq {
@@ -496,6 +499,9 @@ struct kvm_assigned_irq {
 	__u32 host_irq;
 	__u32 guest_irq;
 	__u32 flags;
+	union {
+		__u32 reserved[12];
+	};
 };
 
 #define KVM_DEV_ASSIGN_ENABLE_IOMMU	(1 << 0)