[Skiboot] Upcoming skiboot 5.7.0

[Stewart Smith]

Hi all,

doing the crazy thing that is regular release planning means that
according to
https://github.com/open-power/skiboot/milestones?direction=asc&sort=due_date&state=open

we're getting close to the skiboot 5.7 time, getting in preparation for
op-build v1.18, which is due on July 12th.

So... over the next week, I'll tag an rc or two, and hope people are
able to send any bug fixes for existing code.

-- 
Stewart Smith
OPAL Architect, IBM.