Make serial port on wio-sdk-wm1110 board work

By disabling the (inaccessible) adafruit USB

extra_scripts/README.md

@@ -0,0 +1,3 @@
+# extra_scripts
+
+This directory contains special [scripts](https://docs.platformio.org/en/latest/scripting/index.html) that are used to modify the platformio environment in rare cases.

extra_scripts/disable_adafruit_usb.py

@@ -0,0 +1,17 @@
+Import("env")
+
+# NOTE: This is not currently used, but can serve as an example on how to write extra_scripts
+
+print("Current CLI targets", COMMAND_LINE_TARGETS)
+print("Current Build targets", BUILD_TARGETS)
+print("CPP defs", env.get("CPPDEFINES"))
+
+# Adafruit.py in the platformio build tree is a bit naive and always enables their USB stack for building.  We don't want this.
+# So come in after that python script has run and disable it.  This hack avoids us having to fork that big project and send in a PR
+# which might not be accepted. -@geeksville
+
+env["CPPDEFINES"].remove("USBCON")
+env["CPPDEFINES"].remove("USE_TINYUSB")
+
+# Custom actions when building program/firmware
+# env.AddPreAction("buildprog", callback...)