[llvm] [AMDGPU] Remove TH_BYPASS from CPol (PR #139887)

[Jay Foad via llvm-commits]

jayfoad wrote:

> REAL_BYPASS is confusing though, I don't see the point of that if there's a clear way to tell whether we need to print LU/WB/BYPASS

I don't know what that is for. @mbrkusanin might know.

https://github.com/llvm/llvm-project/pull/139887