[llvm] [llvm-objcopy] Add llvm-objcopy option --set-visibility-sym (PR #80872)

[Ilia Kuklin via llvm-commits]

kuilpd wrote:

> Thanks for the patch! The new option seems reasonable to me, but could you outline what the motivation is for you to have this option? You could after all remove a symbol and readd it with the new visibility as a workaround.
The idea was to have a straightforward option instead of the weird workaround :) Plus it allows for using patterns and even reading them from a file.
> Have you looked at whether GNU objcopy supports this sort of option? If they do, it's important that the option name matches. If they don't, I think the option name should be `--set-symbol-visibility` which would line up better with the `--new-symbol-visibility` option name apart from anything else.
>From what I've seen, it doesn't have anything that changes the visibility of symbols.



https://github.com/llvm/llvm-project/pull/80872