清理Makefile冗余项，各模块Makefile里不需要再次引用公共路径，只需引用私有头文件路径

close: #I49MOO
Signed-off-by: Narvinzzz <zhaotianyu9@huawei.com>
Change-Id: I2dd7189c866498896461f78bfed5444ae1d86876

1. 原kernel/common目录下属于内核拓展组件，统一移入kernel/extend管理
2. Kconfig分层，各模块自己的配置放到自己目录下管理
3. 原platform下不属于平台的公共代码抽到kernel/common下，只留板级链接脚本和一些编译脚本指向device目录下触发平台相关的编译
4. 对外公共头文件统一抽到对外include路径
5. 废弃宏，头文件清理

close: #I48KI4
Signed-off-by: Narvinzzz <zhaotianyu9@huawei.com>
Change-Id: I0cf5ea81c92a8fa7b113da9cbdc8b7bc935f5aae

close: #I44WH1
Signed-off-by: Nmucor <mucorwang@gmail.com>

add BUILD.gn for all kernel modules
Signed-off-by: NCaoruihong <crh.cao@huawei.com>
Change-Id: I018446427bf64615f2596d47862b219659b58b34

1、bootargs解析与rootfs挂载进行解耦；
2、支持开发者自定义bootargs参数，内核存储bootargs中所有参数；
3、开发者可获取bootargs中的参数内容，并自行解析。

close #I41CL8

Change-Id: If384476714854ba0cf64eb70b785eb26737dd3d2
Signed-off-by: Nchenjing <chenjing139@huawei.com>

Signed-off-by: NJoker2770 <1214220480@qq.com>

1.remove redundant headfile in kernel, such as:
  compiler.h;debug.h;automount.h;inode.h;syslog.h;net.h;
2.split fs.h to file.h and driver.h
3.move vnode.h and path_cache.h to vfs/include
4.remove redundant interface and defines

close: #I3RTNR
Signed-off-by: Nmucor <mucorwang@gmail.com>