[lld] [llvm] [LLVM][LTO] Factor out RTLib calls and allow them to be dropped (PR #98512)

[Joseph Huber via llvm-commits]

jhuber6 wrote:

> This does fix a bug where LTO mishandles backends that rename libcalls from the default. Might be worth adding a test that shows that?

Do you have a specific one in mind? I don't know of any cases where the backend renames a libcall that we can trigger.

https://github.com/llvm/llvm-project/pull/98512