manifest: Update hal_nordic with nrf_uarte change

Update hal_nordic with nrf_uarte change. Add functions for setting
PTR and MAXCNT separately.

Signed-off-by: Krzysztof Chruściński <krzysztof.chruscinski@nordicsemi.no>

Author: nordic-krch

west.yml

@@ -200,7 +200,7 @@ manifest:
       groups:
         - hal
     - name: hal_nordic
-      revision: 9587b1dcb83d24ab74e89837843a5f7d573f7059
+      revision: pull/306/head
       path: modules/hal/nordic
       groups:
         - hal