[clang] [RISCV][FMV] Support target_clones (PR #85786)

[Kito Cheng via cfe-commits]

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

LGTM, and I would prefer wait one more LGTM from Craig or Philip *OR* wait one more week to make sure no further comment :)

https://github.com/llvm/llvm-project/pull/85786