manifest: update MCUboot version

Update MCUboot to the version needed for the deprecation of the legacy
stack.

Signed-off-by: Johann Fischer <johann.fischer@nordicsemi.no>

Author: jfischer-no

west.yml

@@ -310,7 +310,7 @@ manifest:
       groups:
         - crypto
     - name: mcuboot
-      revision: 11982df962e2314f4e0c73b7ebc17172026c9266
+      revision: pull/131/head
       path: bootloader/mcuboot
       groups:
         - bootloader