[build] disable vcpkg for Dawn temporarily

Author: fs-eire

cmake/external/onnxruntime_external_deps.cmake

@@ -625,7 +625,11 @@ endif()
 
 
 if (onnxruntime_USE_WEBGPU)
-  if (onnxruntime_USE_VCPKG AND NOT CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
+
+  # the following code is used to disable building Dawn using vcpkg temporarily
+  # until we figure out how to resolve the packaging pipeline failures
+  if (FALSE)
+  # if (onnxruntime_USE_VCPKG AND NOT CMAKE_SYSTEM_NAME STREQUAL "Emscripten")
     # vcpkg does not support Emscripten yet
     find_package(dawn REQUIRED)
   else()

cmake/patches/dawn/dawn_fix_copy_dxil_dll.patch

@@ -0,0 +1,12 @@
+diff --git a/third_party/CMakeLists.txt b/third_party/CMakeLists.txt
+index cdfde38819..c3d70edd05 100644
+--- a/third_party/CMakeLists.txt
++++ b/third_party/CMakeLists.txt
+@@ -350,6 +350,7 @@ function(AddSubdirectoryDXC)
+         add_custom_target(copy_dxil_dll)
+         add_custom_command(
+             TARGET copy_dxil_dll
++            COMMAND ${CMAKE_COMMAND} -E make_directory $<TARGET_FILE_DIR:dxcompiler>
+             COMMAND ${CMAKE_COMMAND} -E copy_if_different ${DXIL_DLL_PATH} $<TARGET_FILE_DIR:dxcompiler>
+             COMMENT "Copying ${DXIL_DLL_PATH} to $<TARGET_FILE_DIR:dxcompiler>")
+         # Make dxc target depend on copy_dxil_dll