!309 修改typo错误

Merge pull request !309 from engine_li/master

en/device-dev/porting/overview-0.md

@@ -42,7 +42,7 @@ The directory structure of the kernel is described as follows:
 │   │   │        └── xxx    --- Implementation of the particular toolchain
 │   │   ├── include         --- Header files that declare the APIs required, kernel-independent
 │   │   └── risc-v          --- RISK_V architecture
-│   │        └── gcc        --- Implementation of the IAR toolchain
+│   │        └── gcc        --- Implementation of the GCC toolchain
 │   ├── include             --- Code for defining the minimum kernel function set
 │   └── src                 --- Code for implementing the minimum kernel function set
 └──utils                    --- Basic code

zh-cn/device-dev/porting/移植概述.md

@@ -42,7 +42,7 @@
 │   │   │        └── xxx    --- xxx编译工具链实现
 │   │   ├── include         --- 所有的arch需要实现的函数定义，内核依赖
 │   │   └── risc-v          --- risk-v架构
-│   │        └── gcc        --- iar编译工具链实现
+│   │        └── gcc        --- gcc编译工具链实现
 │   ├── include             --- 内核最小功能集代码
 │   └── src                 --- 内核最小功能集代码                       
 └──utils                    --- 基础代码，作为依赖的最底层，被系统依赖