the name of the default group is the same with
the directory name.
Signed-off-by: NCaoruihong <crh.cao@huawei.com>
Change-Id: I3d889a361534adc44e3b1bedfec13efe8e1babf2

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

1, this RomFS's codebase is Nuttx romfs, then it is compatible with
Linux RomFS and you can create such a file system using the tool genromfs.
2, there are two major changes against with the original Nuttx romfs:
    1), it is memory-based: all contents of the fs are stored in the
        memory in the very first stage of "mount".
    2), this version of romfs is altered to be compatible with our new
        version of VFS to take advantage of vnode cache and path cache.

close: #I3S0CP

Change-Id: Ia6c1f6302407a707b3ec9b805f4c92d8a7970b86