doc: release: 3.4: add a note about build time priority checking

Add a release note entry about the new build time priority check option.

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>
diff --git a/doc/build/cmake/index.rst b/doc/build/cmake/index.rst
index a59be40..175412a 100644
--- a/doc/build/cmake/index.rst
+++ b/doc/build/cmake/index.rst
@@ -410,6 +410,8 @@
    :start-after: """
    :end-before: """
 
+.. _check_init_priorities.py:
+
 :zephyr_file:`scripts/build/check_init_priorities.py`
 -----------------------------------------------------
 
diff --git a/doc/releases/release-notes-3.4.rst b/doc/releases/release-notes-3.4.rst
index 5fbeffb..7dab44a 100644
--- a/doc/releases/release-notes-3.4.rst
+++ b/doc/releases/release-notes-3.4.rst
@@ -379,6 +379,10 @@
 
 * Twister now supports ``gtest`` harness for running tests written in gTest.
 
+* Added an option to validate device initialization priorities at build time.
+  To use it, enable :kconfig:option:`CONFIG_CHECK_INIT_PRIORITIES`, see
+  :ref:`check_init_priorities.py` for more details.
+
 Drivers and Sensors
 *******************