Use correct directory to extract rootfs

With recent changes to the initramfs the rootfs directory needs to be prefixed with luneos
now instead of webos.

Signed-off-by: Simon Busch <morphis@gravedo.de>
Revert "Include /dev/block path prefix for boot partition by default"

This reverts commit 9841ade3a5436a8801c9563217b06a5e52dcc469.