docs(zephyr): add zephyr version for west init and ocre clone step (project-ocre#140)

Signed-off-by: SorinO <sorin.olari2@gmail.com>

Author: SorinOlari

docs/GetStartedZephyr.md

@@ -64,18 +64,23 @@ The base instructions are based on [Getting Started Guide](https://docs.zephyrpr
 ```sh
 mkdir ~/zephyrproject
 cd ~/zephyrproject
-west init
+west init --mr v4.3.0
 west update
 ```
 
+Now, clone Ocre runtime:
+```sh
+git clone --recurse-submodules https://github.com/project-ocre/ocre-runtime.git
+```
+
 Proceed to the general instructions for Zephyr development below.
 
 ## General instructions
 
 Build a sample:
 
 ```sh
-west build -p always -b native_sim/native/64 src/samples/supervisor/zephyr
+west build -p always -b native_sim/native/64 ocre-runtime/src/samples/supervisor/zephyr
 ```
 
 Make sure you are in a directory inside the Zephyr workspace and the path to the Ocre sample is correct.