Clone this repository in device/nokia/NLA-kernel.
Drop all of these flags in BoardConfig (this is an example):
BOARD_KERNEL_IMAGE_NAME := Image.gz-dtb
TARGET_KERNEL_CLANG_COMPILE := true
TARGET_KERNEL_CONFIG := lineageos_NLA_defconfig
TARGET_KERNEL_SOURCE := kernel/nokia/msm8998
TARGET_KERNEL_VERSION := 4.4
Add this in device makefile:
# Kernel
PRODUCT_COPY_FILES += \
device/nokia/NLA-kernel/kernel:kernel