e2fsprogs: mke2fs: copy files recursively

e2fsprogs: mke2fs: copy files recursively

Use opendir() and readdir() to read the native directory, then use
lstat() to identify the file type and call the corresponding function to
add the file to the filesystem, call the populate_fs() recursively if it
is a directory.

NOTE: the libext2fs can't create the socket file.

[YOCTO #4083]

(From OE-Core rev: fd0d00dafcf497f23b1c3886d062c8a57e2aa515)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>