feat: add support Zephyr v4.2.0, this time for real

Author: MarkoSagadin

.github/workflows/build-and-publish-vanilla-zephyr.yaml

@@ -39,6 +39,9 @@ jobs:
           - zephyr_version: "v4.1.0"
             zephyr_sdk_version: "0.17.4"
             mcuboot_version: "4eba8087fa606db801455f14d185255bc8c49467"
+          - zephyr_version: "v4.2.0"
+            zephyr_sdk_version: "0.17.4"
+            mcuboot_version: "4eba8087fa606db801455f14d185255bc8c49467"
 
     steps:
       - name: Checkout repository

CHANGELOG.md

@@ -6,6 +6,11 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 
 ## [Unreleased]
 
+### Fixed
+
+- Previous release added support only for Zephyr v4.1.0, this one adds support also for
+  Zephyr v4.2.0.
+
 ## [1.17.0] - 2025-08-19
 
 ### Added