manifest: Update nrfxlib for dynamic bandwidth signal controlling

Update nrfxlib for dynamic bandwidth signal controlling through
command init.

Signed-off-by: Kapil Bhatt <[email protected]>

Author: kapbh

west.yml

@@ -142,7 +142,7 @@ manifest:
     - name: nrfxlib
       repo-path: sdk-nrfxlib
       path: nrfxlib
-      revision: v2.6.4
+      revision: pull/1772/head
     - name: trusted-firmware-m
       repo-path: sdk-trusted-firmware-m
       path: modules/tee/tf-m/trusted-firmware-m