modules: hal_nordic: Update nrfx to fix atomic doc

Building documentation in .rst format causes warnings due to
missing nrfx_atomic which is not used in hal_nordic.

Signed-off-by: Nikodem Kastelik <nikodem.kastelik@nordicsemi.no>

west.yml

diff --git a/west.yml b/west.yml
index 43c9d89..12f886d 100644
--- a/west.yml
+++ b/west.yml
@@ -91,7 +91,7 @@
       groups:
         - hal
     - name: hal_nordic
-      revision: 4464a6f96b4a6a1b7ac5ca1b8c3caf6a81d25e57
+      revision: a85bb3676d61d1ae202088e0d3fec556056b2c9e
       path: modules/hal/nordic
       groups:
         - hal