ARM: dts: owl-s500-roseapplepi: Add ethernet support

Add pinctrl configuration for enabling the Ethernet MAC on RoseapplePi
SBC. Additionally, provide the necessary properties for the generic S500
ethernet node in order to setup PHY and MDIO.

Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@gmail.com>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/d0e1fbf81984127f0352eb740c7129424b5e40f9.1623401998.git.cristian.ciocaltea@gmail.com
Link: https://lore.kernel.org/r/20210628072817.8269-3-mani@kernel.org

'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>