[coreboot] Unresolved comments on Gerrit

[Patrick Georgi]

Hi everybody,

you might notice a new column in the Gerrit UI: ACR for All-Comments-Resolved.

For a while, Gerrit allows to "resolve" comments made to changes, and this
field automatically determines if all comments are marked that way.

Another change to our Gerrit install is that changes can only be submitted
when there are no more open comments.

For this reason, please ensure to close comments you consider done.

Thanks,
Patrick