[llvm] [LLVM] Update llvm-objcopy maintainer (PR #120428)

[Fangrui Song via llvm-commits]

MaskRay wrote:

llvm-objcopy is a stable, largely mature drop-in replacement for GNU objcopy, including LLVM extensions.
It is so stable that it doesn't receive much active development.

I suggest that we replace the specific tool llvm-objcopy/ObjCopy with the broader "LLVM binary utilities".
(In addition, we have a `llvm:binary-utilities` new PR label, but not for llvm-objcopy.)

@jh7370 has been the most active reviewer in this area, so I'd like to nominate him as well.
(As we allow multiple maintainers, you may name both of us.)
While James might be less active in patch contribution, his provides invaluable code review, [which is essential to catch potential issues and ensure code maintainability](https://discourse.llvm.org/t/rfc-new-criteria-for-commit-access/76290/5)


https://github.com/llvm/llvm-project/pull/120428