[clang] [clang] Remove FEM_Indeterminable (PR #137661)

[Zahira Ammarguellat via cfe-commits]

zahiraam wrote:

> I think this is a reasonable way forward for right now; we can bring back the enumerator once we're actually using it. WDYT @zahiraam ?

I tend to think so too. But I am waiting for a response from the math library people internally to make sure that we don't loose compatibility with `icc` doing this.

https://github.com/llvm/llvm-project/pull/137661