Support for RTL838x based managed switches

For Developers
1262

@blogic Is there a way to get realtek-poe to be more verbose? PoE stopped working at some point on my GS1900-8HP v1. OEM firmware still powers PoE clients as might be expected. All I'm seeing is the port my PoE client is connected to has its status listed as 'unkown', e.g. here the 1st port. Early on, lowering the power budget (device is specced for 70W ZyXEL says) worked for a bit, but that's not the case anymore.

# ubus call poe info
{
	"firmware": "v17.1",
	"mcu": "ST Micro ST32F100 Microcontroller",
	"budget": 65.000000,
	"consumption": 0.000000,
	"ports": {
		"lan1": {
			"priority": 2,
			"mode": "PoE+",
			"status": "unknown"
		},
		"lan2": {
			"priority": 2,
			"mode": "PoE+",
			"status": "Searching"
		}
	}
}

Configuration:


config global
        option budget   '65'

config port
        option enable   '1'
        option id       '1'
        option name     'lan1'
        option poe_plus '1'
        option priority '2'

config port
        option enable   '1'
        option id       '2'
        option name     'lan2'
        option poe_plus '1'
        option priority '2'