Trust: Onboarding: Listen for locale changes

* When SuW is not yet done, the notification is already posted
* This results in an english notification text when the SuW is finished
  because the notification doesn't update when the locale changes
-> Listen for locale changes and post the notification again (= update)

Change-Id: I920a52c5c85c91adb7333a20d410a5464e80a812