* add extlinux.conf
* - make sure armbianEnv is not added - we don't need variables for NAME_KERNEL and NAME_INITRD. This is not going to change - also MAIN_CMDLINE could at least be renamed so its clear to belong to EXT configuration. Elsewhere this doesn't apply since we have boot scripts
Co-authored-by: Igor Pecovnik <igor.pecovnik@gmail.com>