[llvm] [NVPTX][Docs] [NFC] Update docs on intrinsics (PR #133136)

[Durgadoss R via llvm-commits]

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@@ -153,6 +153,68 @@ Example: 64-bit PTX for CUDA Driver API: ``nvptx64-nvidia-cuda``
 NVPTX Intrinsics
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+Guidelines on NVPTX Intrinsic design
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durga4github wrote:

Moved it to the td file in the latest revision.

https://github.com/llvm/llvm-project/pull/133136