Fix for network-isolated builds
--- a/specification/CMakeLists.txt
+++ b/specification/CMakeLists.txt
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: MIT
 # Copyright (C) 2023 Advanced Micro Devices, Inc.
+if(NOT SPEC_TOOL_DEPS_DOWNLOADED)
 if (${CMAKE_SYSTEM_NAME} STREQUAL "Linux")
   add_custom_target(spec-tool-deps
     COMMAND wget -q -O markdown_graphviz_svg.py
@@ -15,6 +16,10 @@ else()
     WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
     )
 endif()
+else()
+  add_custom_target(spec-tool-deps)
+endif()
+
 
 set(SPEC_PYTHON_PATH ${CMAKE_CURRENT_BINARY_DIR})