set emulate_precision_casts as true for cuda backend for better accuracy (#14983)

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bottom):
* __->__ #14983

as title

Differential Revision:
[D84288174](https://our.internmc.facebook.com/intern/diff/D84288174/)

Author: Gasoonjia

backends/cuda/cuda_backend.py

@@ -129,6 +129,8 @@ def preprocess(
                 user_input_placeholders.append(node.meta["val"])
 
         options: dict[str, typing.Any] = {
+            # Better model precision
+            "emulate_precision_casts": True,
             # Embed CUDA kernel binaries directly into the compiled shared object
             "aot_inductor.embed_kernel_binary": True,
             # Do not link against the full PyTorch/libtorch library