[llvm] [llvm] revisions to `LLVM_ABI` export macro definitions (PR #144598)

[Andrew Rogers via llvm-commits]

andrurogerz wrote:

> We should be building the library a second time if the configuration is different.

I see what you're saying @compnerd. That would be a pretty significant change, so are you OK with this PR as a step in the right direction? It sets up a pattern for doing llvm-c and Demangle as well.

https://github.com/llvm/llvm-project/pull/144598