Dear Maintainer,

I was wondering why upower did not recognize my battery as supporting
charge limits, and I chased down the issue to an existing
/etc/udev/hwdb.bin . Running `systemd-hwdb update` fixed the issue.

As to why it didn't work automagically, I traced it down to the udev
trigger only updating the /usr dabatase.  This means that in practice
the update is ignored by the running udev because the db in /etc takes
precedence.