Update README

Author: christophe0606

README.md

@@ -55,6 +55,7 @@ For any questions or to reach the CMSIS-DSP  team, please create a new issue in
   * [How to build with MDK or Open CMSIS-Pack](#how-to-build-with-mdk-or-open-cmsis-pack)
   * [How to build with Make](#how-to-build-with-make)
   * [How to build with cmake](#how-to-build-with-cmake)
+  * [How to build with Zephyr](#how-to-build-with-zephyr)
   * [How to build with any other build system](#how-to-build-with-any-other-build-system)
   * [How to build for Neon and aarch64](#how-to-build-for-aarch64)
 * [Code size](#code-size)
@@ -155,6 +156,17 @@ Once cmake has generated the makefiles, you can use a GNU Make to build.
 
     make VERBOSE=1
 
+### How to build with Zephyr
+
+Add this to your west file:
+
+```
+- name: cmsis-dsp
+      url: https://github.com/ARM-software/CMSIS-DSP
+      revision: main
+      path: modules/lib/cmsis-dsp
+```
+
 ### How to build with any other build system
 
 You need the following folders: