This makes the LAN port the PoE master, so the AirGateway can be used to
supply power to another node connected via mesh-on-LAN.

Fixes #608

Closes #844

The interfaces were accidentially switched when the CPE210 was separated
from the CPE510 code.

Fixes #121

Based-on-patch-by: Tobias Hachmer <tobias@hachmer.de>

Fixes #764

Also backport some patches improving QCA956x support.

Moving the scripts to a common directory not only vastly simplifies the
zzz-gluon-upgrade script, but also allows to define an ordering of such
scripts across packages.

gluon-config-mode retains the luci frontend, all setup scripts and config is
moved to the new package.