"GNU gperf not found, but it's output appears to be present."

It's using /usr/pkg/* for things like pid and db; not sure if that's
correct.

Not sure that ffmpeg5 is correct

Need to figure out ALSA so mpd mode can be tested.

Config file should be installed into share/examples/owntone and
installed using CONF_FILES

Build and install web interface (separate package?).

Bug https://github.com/owntone/owntone-server/issues/1568 but might
work for someone else.
