DXIL Validator fails to catch reserved OpCode

Description
The DXIL Validator should not allow a reserved DXIL OpCode to be used.

Steps to Reproduce
Try the following validation test that uses a reserved DXIL OpCode. The validator succeeds but should have caught the illegal use of a reserved OpCode.

; RUN: not %dxv %s 2>&1 | FileCheck %s
target datalayout = "e-m:e-p:32:32-i1:32-i8:32-i16:32-i32:32-i64:64-f16:32-f32:32-f64:64-n8:16:32:64"
target triple = "dxil-ms-dx"

define void @main() {
  call void @dx.op.reserved(i32 302)
  ret void
}

; Function Attrs: nounwind
declare void @dx.op.reserved(i32) #0

attributes #0 = { nounwind}

!llvm.ident = !{!0}
!dx.version = !{!1}
!dx.valver = !{!1}
!dx.shaderModel = !{!2}
!dx.resources = !{!3}
!dx.entryPoints = !{!4}

!0 = !{!"hand-crafted"}
!1 = !{i32 1, i32 10}
!2 = !{!"vs", i32 6, i32 10}
!3 = !{null, null, null, null}
!4 = !{void ()* @main, !"main", !5, !3, null}
!5 = !{null, null, null}

Actual Behavior
Validator succeeds, when it should have failed.

Environment

• DXC version latest
• Host Operating System any

Start with the supplied DXIL Validator validation test and run it through dxv to confirm that the reserved opcode is currently accepted. Trace the validator's handling of the reserved DXIL OpCode, then update coverage so the test fails validation and reports the illegal use.