realtek: Clean up and standardize realtek-poe support

realtek:  Clean up and standardize realtek-poe support

This patch cleans up and standardizes realtek-poe support for realtek
based switches that have supported PoE ports.

The power output of switches supported by realtek-poe package can be
configured in the 02_network ucidef_set_poe() function.  This was missed
when some PoE capable switches supported by realtek-poe were added.

The realtek-poe package at one point replaced a lua-rs232 based script
and some devices were not updated to use the realtek-poe package.
Consistently add realtek-poe package to DEVICE_PACKAGES for switches
with supported PoE.

Signed-off-by: Raylynn Knight <rayknight@me.com>