[clang] [llvm] [RISCV] Add generic CPUs for profiles (PR #84877)

[Craig Topper via cfe-commits]

topperc wrote:

> I don't know if we need S-mode profile CPUs.

I lean towards not supporting them since the S extensions don't do anything in the compiler except preprocessor defines and ELF attributes, but maybe we should put it on the agenda for the sync meeting this week.

https://github.com/llvm/llvm-project/pull/84877