ntpdate to openntpd

Greetings,

While looking at dhcpcd Build-Depends, it occurred to me that
timesyncd essentially is an SNTP client that constantly runs in the
background. The only non-Linux equivalent in the Debian repository is
OpenNTPD.

Debian's OpenNTPD package is hopelessly outdated, but I filed a bug of
bug reports that document various fixes that would 1) overhaul the
packaging and 2) package the latest upstream.

As I'm still a mere DM, I cannot perform any QA NMU. Would anyone sponsor it?

Thanks!
Martin-Éric

PS: Mentors apparently is down, so I cannot upload the result there.