Empty bitfield reflection in DXIL

Description
dxc generates invalid reflection for structures with bitfields. This leads to structure parsing issues when using debugging software (PIX, RenderDoc).

Steps to Reproduce

1. Create sample compute shader test.hlsl

StructuredBuffer<float> InputBuffer : register(t0);
RWStructuredBuffer<float> OutputBuffer : register(u0);

struct PPP
{
    uint test : 1;
    uint pad : 31;
};

cbuffer Constants : register(b0)
{
    PPP inner;
};

[numthreads(256, 1, 1)] void main(uint3 DispatchThreadID : SV_DispatchThreadID)
{
    int index = DispatchThreadID.x;

    OutputBuffer[index] = InputBuffer[index] * inner.test;
}

2. Run dxc on it using this command line: dxc.exe -HV 2021 -T cs_6_5 -E main test.hlsl

Actual Behavior
Generated DXIL Buffer Definitions looks like this:

; Buffer Definitions:
;
; cbuffer Constants
; {
;
;   struct Constants
;   {
;
;       struct struct.PPP
;       {
;
;           uint ;                                    ; Offset:    0
;       
;       } inner;                                      ; Offset:    0
;
;   
;   } Constants;                                      ; Offset:    0 Size:     4
;
; }

Expected Behavior

;       struct struct.PPP
;       {
;
;           uint test : 1;                                    ; Offset:    0
;
;           uint pad : 31;                                    ; Offset:    0
;       
;       } inner;                                      ; Offset:    0

Offset: probably should stay the same for the whole uint in bitset.
Environment

• DXC version: dxcompiler.dll: 1.9(5184-21d28f72)(1.9.2602.17) - 1.9.2602.17 (21d28f727)
• Host Operating System: Windows 10

Start with the test.hlsl reproduction and run the provided dxc command to inspect the generated DXIL buffer definitions. Trace the compiler's reflection handling for the PPP bitfield structure. Done means the reflection lists test and pad with their bitfield widths while retaining offset 0 for both fields, without the empty field shown in the report.