To let overlayfs be used like aufs, we create a feature
fragment. Configurations that want this union FS type, can
enable it via KERNEL_FEATURES.
(From OE-Core rev: b5600da9cdbf9a5e3badd990f399591e48b09eae)
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>