[clang] [llvm] [RISCV] Add SpacemiT A100 processor definition (PR #174052)

[Petr Penzin via cfe-commits]

ppenzin wrote:

> It remains unclear whether the final upstream kernel will support this scenario of asymmetric vlen heterogeneity.

Is there a thread on kernel mailing list about that?

https://github.com/llvm/llvm-project/pull/174052