bsp:stm32f4系列 update README.md (#10144)

bsp:stm32f4系列 update README

bsp/stm32/stm32f401-st-nucleo/README.md

@@ -51,6 +51,14 @@ Each peripheral supporting condition for this BSP is as follows:
 
 This BSP provides MDK5 and IAR projects for developers. Also support GCC development environment. Here's an example of the MDK5 development environment, to introduce how to run the system.
 
+**Attention please！！！**
+
+Before the compilation work, please open ENV and execute the following command (this command is used to pull the necessary HAL library and CMSIS library, otherwise it cannot be compiled)：
+
+```bash
+pkgs --update
+```
+
 #### Hardware Connection
 
 Use a Type-A to Mini-B cable to connect the development board to the PC and turn on the power switch. The red LED LD3 (PWR) and LD1 (COM) will lit.

bsp/stm32/stm32f401-st-nucleo/README_zh.md

@@ -62,6 +62,14 @@ STM32F401 Nucleo-64 开发板常用 **板载资源** 如下：
 
 本 BSP 为开发者提供 MDK5 和 IAR 工程，并且支持 GCC 开发环境。下面以 MDK5 开发环境为例，介绍如何将系统运行起来。
 
+**请注意！！！**
+
+在执行编译工作前请先打开ENV执行以下指令（该指令用于拉取必要的HAL库及CMSIS库，否则无法通过编译）：
+
+```bash
+pkgs --update
+```
+
 #### 硬件连接
 
 使用 Type-A to Mini-B 线连接开发板和 PC 供电，红色 LED LD3 (PWR) 和 LD1 (COM) 会点亮。