[compiler-rt] [compiler-rt] Initial support for builtins on GPU targets (PR #95304)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> Distribution is done as LLVM-IR blobs. GPUs have little backward compatibility, so linking object files is difficult.

I'd rather not bake in this assumption. We should be able to support .o and .bc builds 

https://github.com/llvm/llvm-project/pull/95304