[nrf noup] manifest: NCS 2.6.0

Point to the NCS v2.6.0 release tag.

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

Author: jfischer-no

west.yml

@@ -13,5 +13,5 @@ manifest:
     - name: nrf
       remote: ncs
       repo-path: sdk-nrf
-      revision: main
+      revision: v2.6.0
       import: true