[llvm] [DXIL] Add GroupMemoryBarrierWithGroupSync intrinsic (PR #114349)

[Adam Yang via llvm-commits]

adam-yang wrote:

Regarding the warnings:
- The `switch which covers all enumeration values` warning was resolved by removing the `default`.
- The `must specify at least one argument for '...' parameter of variadic macro` warning was resolved by doing what `DXIL_OP_FUNCTION_TYPE` did, which used the same variadic parameter mechanism, but leaves empty ones like `DXIL_OP_FUNCTION_TYPE(dxil::OpCode::WaveIsFirstLane, dxil::OpParamType::Int1Ty, )` which satisfies the compiler.

https://github.com/llvm/llvm-project/pull/114349