There will be some .mk file where you need to put code to copy files to the android system.
# file copy PRODUCT_COPY_FILES += \ device/softwinner/nanopi-h3/extras/kernelService:system/bin/kernelService \ device/softwinner/nanopi-h3/extras/kernelService.sh:system/bin/kernelService.sh \ device/softwinner/nanopi-h3/extras/usr/share/ac.conf:system/usr/share/config.conf
Now in init.rc
#service for kernel commands like service someName /system/bin/kernelService.sh class main oneshot