west.yml: Update zephyr revision

Update zephyr revision to bring smp_svr configuration for
nrf5340dk_nrf5340.

Signed-off-by: Dominik Ermel <[email protected]>

Author: de-nordic

west.yml

@@ -50,7 +50,7 @@ manifest:
     # https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/guides/modules.html
     - name: zephyr
       repo-path: sdk-zephyr
-      revision: v3.1.99-ncs1
+      revision: pull/909/head
       import:
         # In addition to the zephyr repository itself, NCS also
         # imports the contents of zephyr/west.yml at the above