manifest: Update sdk-nrf revision after PDN deprecation

Update the sdk-nrf revision after PDN library has been
deprecated. The LTE net interface now uses PDN via LTE LC.

Signed-off-by: Jan Tore Guggedal <jantore.guggedal@nordicsemi.no>

Author: jtguggedal

west.yml

@@ -14,5 +14,5 @@ manifest:
     - name: nrf
       remote: ncs
       repo-path: sdk-nrf
-      revision: fd20d7a44cf2361183b6b2dbdb79b5aff82fbd03
+      revision: pull/25644/head
       import: true