[llvm] [RISCV] Prefer (select (x < 0), y, z) -> x >> (XLEN - 1) & (y - z) + z even with Zicond. (PR #125772)

[Yingwei Zheng via llvm-commits]

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

LGTM. Thank you!
Please add some tests to demonstrate the change.

https://github.com/llvm/llvm-project/pull/125772