[llvm] [AMDGPU] Add AMDGPU support for llvm-objcopy (PR #92066)

[Aakanksha Patil via llvm-commits]

aakanksha555 wrote:

> There's a problem with obj2yaml now, which should be fairly trivial to fix. Also, could you split off the yaml2obj/obj2yaml changes into a separate PR, that this one relies on, please? It's functionally useful on its own.

https://github.com/llvm/llvm-project/pull/143845

Split up the "FLAGS=<none>" changes in the above PR

https://github.com/llvm/llvm-project/pull/92066