more inputs support for LLM exporter (microsoft#19005)

### Description
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### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->

Author: wejoncy

onnxruntime/python/tools/transformers/large_model_exporter.py

@@ -224,24 +224,35 @@ def fetch_onnx_inputs_outputs_name(
     if not num_of_past_key:
         num_of_past_key = model.config.num_hidden_layers
 
-    onnx_inp_names = ("input_ids", "attention_mask")
+    # filter out constant inputs
+    onnx_inp_names = tuple(
+        [torch_input_names[i] for i in range(len(torch_input_names)) if isinstance(onnx_inputs[i], torch.Tensor)]
+    )
+    assert (
+        "input_ids" in onnx_inp_names and "attention_mask" in onnx_inp_names
+    ), "input_ids and attention_mask must be existed in inputs"
     onnx_out_names = ("logits",)
     onnx_dynamic_axes = {
         "input_ids": {0: "batch_size", 1: "seq_len"},
         "attention_mask": {0: "batch_size", 1: "seq_len"},
     }
+    # add dyanmic dimensions for the unkonw inputs
+    for idx, name in enumerate(onnx_inp_names):
+        if name not in onnx_dynamic_axes:
+            unknown_dims = {i: f"{idx}__unknown_dims__{i}" for i in range(onnx_inputs[idx].dim())}
+            onnx_dynamic_axes[name] = unknown_dims
     if input_with_past:
         for i in range(num_of_past_key):
-            onnx_inp_names += (f"present_key.{i}",)
-            onnx_inp_names += (f"present_values.{i}",)
+            onnx_inp_names += (f"past_key_values.{i}.key",)
+            onnx_inp_names += (f"past_key_values.{i}.value",)
 
             onnx_dynamic_axes[onnx_inp_names[-1]] = kv_cache_axis
             onnx_dynamic_axes[onnx_inp_names[-2]] = kv_cache_axis
 
     if with_past or input_with_past:
         for i in range(num_of_past_key):
-            onnx_out_names += (f"past_key.{i}",)
-            onnx_out_names += (f"past_values.{i}",)
+            onnx_out_names += (f"present.{i}.key",)
+            onnx_out_names += (f"present.{i}.value",)
             onnx_dynamic_axes[onnx_out_names[-1]] = kv_cache_axis
             onnx_dynamic_axes[onnx_out_names[-2]] = kv_cache_axis