arm64: dts: qcom: sa8775p-ride: add pin functions for ethernet0

Add the MDC and MDIO pin functions for ethernet0 on sa8775p-ride.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Tested-by: Andrew Halaney <ahalaney@redhat.com>
Link: https://lore.kernel.org/r/20230622120142.218055-5-brgl@bgdev.pl


Signed-off-by: Bjorn Andersson <andersson@kernel.org>