[clang] [llvm] [RISCV] Add support for getHostCPUFeatures using hwprobe (PR #94352)

[Yingwei Zheng via cfe-commits]

dtcxzyw wrote:

I have no idea about why it corrupts StringMap. Sad :(

![image](https://github.com/llvm/llvm-project/assets/15650457/fd427068-6ca0-4ecb-a340-48c51e5629a6)


https://github.com/llvm/llvm-project/pull/94352