KVM: x86: Add a VM type define for TDX

Add a VM type define for TDX.

Future changes will need to lay the ground work for TDX support by
making some behavior conditional on the VM being a TDX guest.

Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Message-ID: <20240718211230.1492011-4-rick.p.edgecombe@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Author: rpedgeco

arch/x86/include/uapi/asm/kvm.h

@@ -925,5 +925,6 @@ struct kvm_hyperv_eventfd {
 #define KVM_X86_SEV_VM		2
 #define KVM_X86_SEV_ES_VM	3
 #define KVM_X86_SNP_VM		4
+#define KVM_X86_TDX_VM		5
 
 #endif /* _ASM_X86_KVM_H */