ARM: dts: sun8i: h3: bpi-m2-plus: Fix address for external RGMII Ethernet PHY

The external RTL8211E RGMII Ethernet PHY is configured via external
resistors to use the address 0x1. The 0x0 address is a broadcast address
for this family of PHYs, and should not be used explicitly.

Fixes: 8c7ba536 ("ARM: sun8i: bananapi-m2-plus: Enable dwmac-sun8i")
Fixes: 4904337f ("ARM: dts: sunxi: Restore EMAC changes (boards)")
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Chen-Yu Tsai <wens@csie.org>