[llvm] [IR] `select` should reject token-like types (PR #219162)

[Sameer Sahasrabuddhe via llvm-commits]

ssahasra wrote:

As presented in [this discussion](https://discourse.llvm.org/t/directx-and-the-semantics-of-target-extension-types/91708), token-like target extension types don't seem to have a real use, and are hard to implement. I'll hold this change and instead pursue removing the token-like property entirely.

https://github.com/llvm/llvm-project/pull/219162