update readme

selfdrive/modeld/models/README.md

@@ -20,7 +20,11 @@ To view the architecture of the ONNX networks, you can use [netron](https://netr
 * **traffic convention**
   * one-hot encoded vector to tell model whether traffic is right-hand or left-hand traffic : 2
 * **feature buffer**
-  * A buffer of intermediate features that gets appended to the current feature to form a 5 seconds temporal context (at 20FPS) : 99 * 128
+  * A buffer of intermediate features that gets appended to the current feature to form a 5 seconds temporal context (at 20FPS) : 99 * 512
+* **nav features**
+  * 1 * 150
+* **nav instructions**
+  * 1 * 256
 
 
 ### Supercombo output format (Full size: XXX x float32)