Merge "Remove stale SYSTEM_ROOT_IMAGE board config for old kernels" am: 59d1eb18e3

Original change: https://android-review.googlesource.com/c/device/linaro/hikey/+/2176482

Change-Id: Ia2395bf9ce9902b8eaa0723e3ea63c7b8db5a167
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>