add auto select "espidf" when pio var "custom_sdkconfig" is set

Author: Jason2866

platform.py

@@ -39,6 +39,9 @@ def configure_default_packages(self, variables, targets):
         mcu = variables.get("board_build.mcu", board_config.get("build.mcu", "esp32"))
         frameworks = variables.get("pioframework", [])
 
+        if variables.get("custom_sdkconfig") is not None:
+            frameworks.append("espidf")
+
         if "arduino" in frameworks:
             self.packages["framework-arduinoespressif32"]["optional"] = False
             self.packages["framework-arduinoespressif32-libs"]["optional"] = False