AMD GFX941 & GFX942 GPU Targets Added To LLVM Compiler

Going back to last year there's been AMD GFX940 work within the LLVM compiler for its AMDGPU compiler back-end. That AMD GFX940 should align to the Instinct MI300 while introduced to the latest LLVM compiler code today are new GFX941 and GFX942 targets...