Clean-up Onyx headings

Android-tips-and-tricks.md

@@ -70,7 +70,9 @@ To enable the USB driver on your device, follow these general steps:
 
 Note: The exact steps may vary slightly depending on your device model and Android version.
 
-### Onyx Devices Permission
+### Onyx Devices
+
+#### Light drivers, permissions
 
 For Onyx devices running Android version 11 and above, these additional steps are necessary to enable the Lights driver. These steps are essential because certain methods are restricted due to limitations on non-SDK interfaces:
 
@@ -88,6 +90,9 @@ For Onyx devices running Android version 11 and above, these additional steps ar
     ```bash
     adb shell settings delete global hidden_api_policy
     ```
+
+#### Other settings
+
 **Enable USB debugging**: Apps > top right hamburger icon > App Management > USB Debug Mode: enable
 
 **Enable orientation change within KOReader**: Apps > top right hamburger icon > App Management > Force to follow system orientation > KOReader: disable