[DRAFT] implement multiboot menu based on extlinux

[hitechshell]

[hitechshell]

its work, but code seems a bit ugly.

[TravMurav]

Hi! Unfortunately I'm currently opposed to adding any kind of interactive boot menus to lk2nd. I believe such system gets incredibly hard to implement properly and creates a lot of unobvious edge cases, especially in lk2nd's most common usecases. As such, for lk2nd we decided to draw a "line in the sand" on only allowing a single boot entry with a very rigid priority and instead encourage people to contribute to bootloaders which are better suited for multiboot long term, such as u-boot (which would allow you to use any EFI capable bootloader/system)

[hitechshell]

Hmm, okay. Unfortunately, porting u-boot will take significantly more time, but I understand your point. Perhaps when I have a little more free time, I'll implement the lk2nd-like UI (it looks really convenient) for u-boot.

Perhaps we should close this PR as not-planned?