west.yml: update Zephyr to c8b9adaec98

Updates Zephyr to bring in UAOL support.

Signed-off-by: Serhiy Katsyuba <serhiy.katsyuba@intel.com>

Author: serhiy-katsyuba-intel

west.yml

@@ -43,7 +43,7 @@ manifest:
 
     - name: zephyr
       repo-path: zephyr
-      revision: 653ebccc49ad1f79cae2729f4c6fabd5ff54d397
+      revision: c8b9adaec98778767d00a41bbb395eabe9f4985e
       remote: zephyrproject
 
       # Import some projects listed in zephyr/west.yml@revision