RPB had moved from jethro to krogoth quite some time ago. Having "jethro"
in the instructions causes confusion.
Signed-off-by: Andrey Konovalov <andrey.konovalov@linaro.org>
On HiKey /dev/mmcblk0p9 (the partition used to store rootfs) is
named 'system', not 'rootfs'.
Signed-off-by: Andrey Konovalov <andrey.konovalov@linaro.org>