add env var esp-rom-elfs

Author: Jason2866

builder/frameworks/espidf.py

@@ -536,6 +536,8 @@ def populate_idf_env_vars(idf_env):
     if "IDF_TOOLS_PATH" in idf_env:
         del idf_env["IDF_TOOLS_PATH"]
 
+    idf_env["ESP_ROM_ELF_DIR"] = platform.get_package_dir("tool-esp-rom-elfs")
+
 
 def get_target_config(project_configs, target_index, cmake_api_reply_dir):
     target_json = project_configs.get("targets")[target_index].get("jsonFile", "")