[llvm] [LoongArch] Combine FP_TO_UINT/FP_TO_SINT with [X]VFTINTRZ instruction (PR #201569)

[via llvm-commits]

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wangleiat wrote:

We can use `--check-prefixes=CHECK,LAxx`  here to reduce the amount of changes needed in the test cases.

https://github.com/llvm/llvm-project/pull/201569