The timeout of 90s was introduced before it was ensured that the timesync
systemd unit starts after network is online. Now with that, it makes less sense
to wait that long - if network is unreachable at the point the time
synchronization starts, and the server fails to reply on the first sync, the
polling interval is exponentially increased and the benefit of waiting for more
attempts is doubtful.
Since another synchronization attempt is done after network changes its state,
we should rely on that instead of having the 90 seconds interval as a waiting
period for plugging the network cable. Worst case, there are other mechanisms
that should set the time to a reasonably accurate value, making the NTP sync
less importart for most of the cases.
* Relocate HAOS Systemd drop-ins to /usr/lib/systemd
With some exceptions, Systemd drop-ins overriding default unit configuration
have been placed to `/etc/systemd/system`. This is meant for user overrides of
those, or per `man 5 systemd.unit` for "system unites created by the
administrator". Relocate all of these to `/usr/lib/systemd` which should be
used as path for units "installed by the distribution package manager" which is
closer to what we're trying to achieve.
This will make it easier to detect changes to unit files once we enable the
possibility to edit the content of /etc.
* Patch systemd-timesyncd.service instead of replacing it fully
