[llvm] [RISCV] Correct the cost model for the i1 reduce.add and reduce.or. (PR #122349)

[Shao-Ce SUN via llvm-commits]

https://github.com/sunshaoce approved this pull request.

LGTM. I think this can land before https://github.com/llvm/llvm-project/pull/119160.

https://github.com/llvm/llvm-project/pull/122349