1、生成JN-mini5728配置文件
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- JN-mini5728_defconfig
2、编译JN-mini5728设备树
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- JN-mini5728.dtb
3、编译JN-mini5728内核
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- zImage -j4
4、编译JN-mini5728内核大概需要8分钟，编译成功后，
arch/arm/boot/dts/JN-mini5728.dtb为设备树镜像
arch/arm/boot/zImage为Linux内核镜像
