[lld] [LLD][ELF] Support 'i' and 'l' memory region attributes (PR #110937)

[Fangrui Song via llvm-commits]

MaskRay wrote:

Clang has to support many GCC options to attract users, which also adds some burden.

In contrast, we set a higher standard for lld. Before it gained widespread recognition, we focused on appealing to users from FreeBSD, Android, the Linux kernel, and more.
Our goal was to identify genuinely useful features rather than simply adding capabilities for specific applications.

I'd like to see useful usage of `i` `l`, not just legitimate usage. I personally believe it is both niche and error-prone.

https://github.com/llvm/llvm-project/pull/110937