[clang] [llvm] [RISCV] Add Hazard3 CPU (PR #102452)

[Sam Elliott via cfe-commits]

lenary wrote:

I've reached out to Luke to ask his/RPi's opinion (but I think he might be away at the moment, so a reply might be slow). My preference remains `raspberrypi-rp2350` because it matches our `<vendor>-<id>` approach taken so far (for everything except rocket).

https://github.com/llvm/llvm-project/pull/102452