west.yml: Update hal_silabs revision

Last version of hal_silabs reduces the number of patches applied on
upstream SDKs.

Signed-off-by: Jérôme Pouiller <[email protected]>

Author: jerome-pouiller

west.yml

@@ -240,7 +240,7 @@ manifest:
       groups:
         - hal
     - name: hal_silabs
-      revision: 5d75cba8a1b0e9a747ae387d9ffbb1bf7cd8c529
+      revision: pull/151/head
       path: modules/hal/silabs
       groups:
         - hal