remove NCHWC data layout - it did not seem to be used. add prefix for OrtEpDataLayout members.

Author: edgchen1

include/onnxruntime/core/framework/execution_provider.h

@@ -62,7 +62,6 @@ using RunOptions = ::OrtRunOptions;
 enum class DataLayout {
   NCHW,
   NHWC,
-  NCHWC,
 };
 
 class IExecutionProvider {

include/onnxruntime/core/session/onnxruntime_ep_c_api.h

@@ -140,9 +140,8 @@ struct OrtEpApi {
  * \since Version 1.23.
  */
 typedef enum OrtEpDataLayout {
-  NCHW = 0,
-  NHWC,
-  NCHWC,
+  OrtEpDataLayout_NCHW = 0,
+  OrtEpDataLayout_NHWC,
 } OrtEpDataLayout;
 
 /**

onnxruntime/core/session/ep_plugin_provider_interfaces.cc

@@ -281,15 +281,12 @@ DataLayout PluginExecutionProvider::GetPreferredLayout() const {
   ORT_THROW_IF_ERROR(ToStatusAndRelease(ort_ep_->GetPreferredDataLayout(ort_ep_.get(), &api_data_layout)));
 
   switch (api_data_layout) {
-    case OrtEpDataLayout::NCHW:
+    case OrtEpDataLayout::OrtEpDataLayout_NCHW:
       return DataLayout::NCHW;
 
-    case OrtEpDataLayout::NHWC:
+    case OrtEpDataLayout::OrtEpDataLayout_NHWC:
       return DataLayout::NHWC;
 
-    case OrtEpDataLayout::NCHWC:
-      return DataLayout::NCHWC;
-
     default:
       ORT_THROW("OrtEp::GetPreferredDataLayout() returned an invalid data layout: ",
                 static_cast<int>(api_data_layout));

onnxruntime/test/framework/ep_plugin_provider_test.cc

@@ -82,7 +82,7 @@ TEST(PluginExecutionProviderTest, GetPreferredLayout) {
 
   {
     auto prefer_nhwc_fn = [](OrtEp* /*this_ptr*/, OrtEpDataLayout* preferred_data_layout) -> ::OrtStatus* {
-      *preferred_data_layout = OrtEpDataLayout::NCHW;
+      *preferred_data_layout = OrtEpDataLayout::OrtEpDataLayout_NCHW;
       return nullptr;
     };
     ort_ep->GetPreferredDataLayout = prefer_nhwc_fn;