stand/efi: Allow RELAXED or STRICT boot policies

[imp]

Summary

The RELAXED boot policy will automatically search for any root
filesystem (currently zfs only) on any device. STRICT policy only
searches on the boot device.

Sponsored by: Netflix

[imp]

assume the boot dev are first on list.

[imp]

lookup table for values.

[imp]

Oh, I don't need the on_bootdev stuff. Simplify.

[imp]

Oh, don't make silly changes, so we're down to main.c only now.

[glebius]

stand/efi/loader/main.c

151–154

This will make two declarations better coupled together.

614–616

Didn't you you want to skip entries that don't match the condition instead of breaking the cycle? What if next entry is actually the one we want?

[glebius]

stand/efi/loader/main.c

614–616

Now that I've seen your change to D55094, I see that there is no difference between breaking the cycle or skipping entries. So whatever works. But in case if you prefer breaking the cycle, I will suggest to put a comment explaining why we sure that no good entry is there in the list, referencing the other file.

[imp]

stand/efi/loader/main.c

614–616

I think that continue w/o head-insert is better and simpler, so I'll do that. Thanks for the suggestion.