udpdate porting-linux-kernel.md

Signed-off-by: Nester.zhou <ester.zhou@huawei.com>

en/device-dev/porting/porting-linux-kernel.md

@@ -114,6 +114,13 @@ source "drivers/staging/hilog/Kconfig"
 source "drivers/staging/hievent/Kconfig"
 ```
 
+Add the following code to the third-party kernel file **Makefile** in the **drivers/staging** directory:
+
+```
+obj-$(CONFIG_HILOG)             += hilog/
+obj-$(CONFIG_HIEVENT)           += hievent/
+```
+
 Enable the CONFIG macros **CONFIG\_HILOG** and **CONFIG\_HIEVENT** in the kernel **config** section.
 
 For details about how to use the logs, see [Hilog\_lite](https://gitee.com/openharmony/hiviewdfx_hilog_lite/blob/master/README.md).