LWJGLOpenVRInput: solve a javadoc warning

jme3-vr/src/main/java/com/jme3/input/vr/lwjgl_openvr/LWJGLOpenVRInput.java

@@ -683,7 +683,7 @@ public class LWJGLOpenVRInput implements VRInputAPI {
      * If a cached handle is available it is returned, if not it is fetched from openVr
      *
      * @param inputName the input name, e.g. /user/hand/right. Or null, which means "any input"
-     * @return
+     * @return the input handle
      */
     public long getOrFetchInputHandle( String inputName ){
         if(!inputHandles.containsKey(inputName)){