[llvm-branch-commits] [DirectX] Differentiate between 0/1 overloads in the OpBuilder. NFC (PR #104246)

[Justin Bogner via llvm-branch-commits]

https://github.com/bogner created https://github.com/llvm/llvm-project/pull/104246

DXIL operations that only have one signature behave one of two ways - either
they are always suffixed with a type like `dx.op.ThreadId.i32` and hence have
exactly one overload, or they're never suffixed like `dx.op.CreateHandle` and
hence have zero overloads.

Update DXIL.td for operations that have one overload and remove the hack in the
builder that was adjusting names for unoverloaded ops.