[clang] [llvm] [OpenMP] Remove 'libomptarget.devicertl.a' fatbinary and use static library (PR #126143)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> > We already have a host-side libomptarget:
> 
> +1, though as @jhuber6 mentioned, we did name it prefix with `libomptarget-nvptx64` or `libomptarget-amdgcn` before. I think this is a great opportunity to make it more appropriate. However, I don't have strong opinion against it.

It's called `libompdevice.a` now.

https://github.com/llvm/llvm-project/pull/126143