Remove genext2fs since we don't use it anymore, it can't support
ext4 well, either. We have used "mke2fs -d" to instead of it.
[YOCTO #6013]
(From OE-Core rev: ff5666bc460520aef6105e117d5431c05fd9f55b)
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>