[yocto] update mechanisms

[Kristian Amlie]

On 09/12/16 16:13, Patrick Ohly wrote:
> Kristian, I added a comment that Mender requires U-Boot. That is
> correct, isn't it? I understand that this restriction allows you to
> implement things like automatic rollback, but it's worth mentioning that
> this comes with that limitation.

Yes, that is correct, I should have added it the first time around.

-- 
Kristian