Change the way the "magic-packet" DT property is handled in the
macb_probe() function, matching DT binding documentation.
Now we mark the device as "wakeup capable" instead of calling the
device_init_wakeup() function that would enable the wakeup source.

For Ethernet WoL, enabling the wakeup_source is done by
using ethtool and associated macb_set_wol() function that
already calls device_set_wakeup_enable() for this purpose.

That would reduce power consumption by cutting more clocks if
"magic-packet" property is set but WoL is not configured by ethtool.

Fixes: 3e2a5e15 ("net: macb: add wake-on-lan support via magic packet")
Cc: Claudiu Beznea <claudiu.beznea@microchip.com>
Cc: Harini Katakam <harini.katakam@xilinx.com>
Cc: Sergio Prado <sergio.prado@e-labworks.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>