Update Zephyr to v4.2.1

Author: valeros

platform.json

@@ -298,7 +298,7 @@
       "type": "framework",
       "optional": true,
       "owner": "platformio",
-      "version": "~3.40200.0"
+      "version": "~3.40201.0"
     },
     "tool-stm32flash": {
       "type": "uploader",