[llvm] [llvm-objcopy] Don't remove .gnu_debuglink section when using --strip-all (PR #78919)

[Felix Kellenbenz via llvm-commits]

felixkellenbenz wrote:

@jh7370 I made the requested changes.

I replaced the #NNNNN with a link but it seems link git hub automatically converts it to #NNNNN.

https://github.com/llvm/llvm-project/pull/78919