ARM: sun8i: h3: Enable EMAC with external PHY on Orange Pi Plus 2E

ARM: sun8i: h3: Enable EMAC with external PHY on Orange Pi Plus 2E

The Orange Pi Plus 2E, unlike the Orange Pi PC and PC Plus which its
schematics are based on, uses an external Realtek RTL8211E PHY in
RGMII mode, with a GPIO enabling the regulator for I/O signalling
power supplies. The PHY's main power supply is enabled by the main
5V power supply.

Add the regulator and PHY nodes, and override the PHY phandle under
the EMAC node, so that the EMAC works properly on this board.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>