[HLSL][SPIRV][DXIL] Implement `WaveActiveSum` intrinsic (#118580)

``` - add clang builtin to Builtins.td
- link builtin in hlsl_intrinsics
- add codegen for spirv intrinsic and two

[HLSL][SPIRV][DXIL] Implement `WaveActiveSum` intrinsic (#118580)

``` - add clang builtin to Builtins.td
- link builtin in hlsl_intrinsics
- add codegen for spirv intrinsic and two directx intrinsics to retain
signedness information of the operands in CGBuiltin.cpp
- add semantic analysis in SemaHLSL.cpp
- add lowering of spirv intrinsic to spirv backend in
SPIRVInstructionSelector.cpp
- add lowering of directx intrinsics to WaveActiveOp dxil op in
DXIL.td

- add test cases to illustrate passespendent pr merges.
```
Resolves #70106

---------

Co-authored-by: Finn Plummer <canadienfinn@gmail.com>

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