Build: Port b_u585i_iot02A on split build

Change-Id: I88e54e43a9b3289735f385513f956a5dbfe74945
Signed-off-by: Michel JAOUEN <michel.jaouen@st.com>
diff --git a/docs/platform/stm/common/stm32u5xx/readme.rst b/docs/platform/stm/common/stm32u5xx/readme.rst
index 97c34f9..9db6e52 100644
--- a/docs/platform/stm/common/stm32u5xx/readme.rst
+++ b/docs/platform/stm/common/stm32u5xx/readme.rst
@@ -34,7 +34,7 @@
 
 Write software on target
 ^^^^^^^^^^^^^^^^^^^^^^^^
-In build folder:
+In secure build folder directory api_ns:
 
   - ``postbuild.sh``: Updates regression.sh and TFM_UPDATE.sh scripts according to flash_layout.h
   - ``regression.sh``: Sets platform option bytes config and erase platform