[components/net/lwip-1.4.1] 修复不开启 RT_USING_LIBC 时 errno 错误码重复定义的问题

Signed-off-by: MurphyZhao <d2014zjt@163.com>

components/net/lwip-1.4.1/src/arch/include/arch/cc.h

@@ -64,8 +64,6 @@ typedef uintptr_t mem_ptr_t;
 			in arch.h has been assigned to another error code. */
 #define ESHUTDOWN 180
 #endif /* __CC_ARM/__IAR_SYSTEMS_ICC__ */
-#else
-#define LWIP_PROVIDE_ERRNO
 #endif
 
 #if defined(RT_USING_LIBC) || defined(RT_USING_MINILIBC)