[nrf fromlist] manifest: update hal_nordic revision

The nrfx sample applications now enable nrfx_gppi functionality
explicitly.

Upstream PR #: 82842

Signed-off-by: Rafał Kuźnia <[email protected]>

Author: e-rk

west.yml

@@ -188,7 +188,7 @@ manifest:
       groups:
         - hal
     - name: hal_nordic
-      revision: 54bde38c6f6ffb3780b26ae728cf79426184384e
+      revision: pull/268/head
       path: modules/hal/nordic
       groups:
         - hal