[clang] [llvm] [HLSL] Re-implement countbits with the correct return type (PR #113189)

[Justin Bogner via cfe-commits]

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@@ -553,11 +553,10 @@ def Rbits :  DXILOp<30, unary> {
   let attributes = [Attributes<DXIL1_0, [ReadNone]>];
 }
 
-def CBits :  DXILOp<31, unary> {
+def CBits :  DXILOp<31, unaryBits> {
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bogner wrote:

Can we rename this to CountBits while we're at it? It's best if the OpCode names here match the existing [DXIL docs](https://github.com/microsoft/DirectXShaderCompiler/blob/main/docs/DXIL.rst#countbits) and the names used in DXC

https://github.com/llvm/llvm-project/pull/113189