[compiler-rt] [RISCV][compiler-rt] create __riscv__cpu_model for vendorID, ArchID, … (PR #101449)

[Kito Cheng via llvm-commits]

https://github.com/kito-cheng approved this pull request.

LGTM, and I believe this modification will allow us to quickly extend the `cpu=` or `tune=` syntax in the future :)


https://github.com/llvm/llvm-project/pull/101449