fix: ReadMe中无对动态加载模块待加载的共享库的限制说明。

背景：动态加载模块需要确保待加载共享库的安全性，由用户保证。

close #I4ICK8
Signed-off-by: NHaryslee <lihao189@huawei.com>
Change-Id: I6390ab3059ce6d134669c62a14f913e5b09b291d

README.md

@@ -48,6 +48,8 @@ OpenHarmony LiteOS-M supports only C and C++.
 
 It applies only to Cortex-M3, Cortex-M4, Cortex-M7, and RISC-V chip architectures.
 
+As for dynamic loading module, the shared library to be loaded needs signature verification or source restriction to ensure security.
+
 ## Usage<a name="section3732185231214"></a>
 
 The OpenHarmony LiteOS-M kernel build system is a modular build system based on Generate Ninja (GN) and Ninja. It supports module-based configuration, tailoring, and assembling, and helps you build custom products. This document describes how to build a LiteOS-M project based on GN and Ninja. For details about the methods such as GCC+Makefile, IAR, and Keil MDK, visit the community websites.

README_zh.md

@@ -46,6 +46,8 @@ OpenHarmony LiteOS-M内核是面向IoT领域构建的轻量级物联网操作系
 
 适用架构：当前只适用于cortex-m3、cortex-m4、cortex-m7、risc-v芯片架构。
 
+动态加载模块：待加载的共享库需要验签或者限制来源，确保安全性。
+
 ## 使用说明<a name="section3732185231214"></a>
 
 OpenHarmony LiteOS-M内核的编译构建系统是一个基于gn和ninja的组件化构建系统，支持按组件配置、裁剪和拼装，按需构建出定制化的产品。本文主要介绍如何基于gn和ninja编译LiteOS-M工程，GCC+Makefile、IAR、Keil MDK等编译方式可以参考社区爱好者贡献的站点。