Success updating stable/11 to /12; a couple things to note

[Ian Lepore]

On Thu, 2018-12-27 at 05:53 -0800, David Wolfskill wrote:
> * I found that I actually needed to create the ntpd user on the
>   running system prior to "make installworld" -- having run
>   "mergemaster -U" against the target (DESTDIF) was insufficient.

The correct update sequence involves running mergemaster twice, once
with the -p option, then again later without it. It's detailed at the
bottom of UPDATING. People get in the habit of skipping the -p step
because it's only really needed once every few years, such as when a
new user is added to the base system.

-- Ian