update docs

Signed-off-by: Nannie_wangli <annie.wangli@huawei.com>

en/device-dev/subsystems/Readme-EN.md

@@ -39,14 +39,14 @@
     - [KWS SDK](subsys-aiframework-demo-sdk.md)
     - [KWS Plug-in](subsys-aiframework-demo-plugin.md)
     - [KWS Configuration File](subsys-aiframework-demo-conf.md)
+- [Data Management](subsys-database.md)
+  - [RDB](subsys-database-relational.md)
+    - [RDB Overview](subsys-database-relational-overview.md)
+    - [RDB Development](subsys-database-relational-guide.md)
 - [Sensors](subsys-sensor.md)
   - [Sensors Overview](subsys-sensor-overview.md)
   - [Sensors Usage Guidelines](subsys-sensor-guide.md)
   - [Sensors Usage Example](subsys-sensor-demo.md)
-- [USB](subsys-usbservice.md)
-  - [[USB Overview](subsys-usbservice-overview.md)
-  - [USB Usage Guidelines](subsys-usbservice-guide.md)
-  - [USB Usage Example](subsys-usbservice-demo.md)
 - [Application Framework](subsys-application-framework.md)
   - [Overview](subsys-application-framework-overview.md)
   - [Setting Up a Development Environment](subsys-application-framework-envbuild.md)

en/device-dev/subsystems/subsys-data-relational-database.md

+# RDB
+
+- **[RDB Overview](subsys-data-relational-database-overview.md)**
+
+- **[RDB Development](subsys-data-relational-database-guide.md)**

en/device-dev/subsystems/subsys-data.md

+# Data Management
+
+-   **[RDB](subsys-data-relational-database.md)**
+-   **[Lightweight Data Store](subsys-data-storage.md)**