[llvm] [VP][RISCV] Introduce vp.lrint/llrint and RISC-V support. (PR #82627)

[Yeting Kuo via llvm-commits]

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yetingk wrote:

I am sorry it is caused by I forgot to update the fixed vector test cases. vp.lrint/llrint does not encounter the same problem as lrint/llrint.

https://github.com/llvm/llvm-project/pull/82627