arm64: dts: qcom: ipq8074: add clock-frequency to MDIO node

Add clock-frequency to MDIO node to set the MDC rate to 6.25Mhz instead
of using the default value of 390KHz from MDIO default divider.
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Link: https://lore.kernel.org/r/20240131022731.2118-1-ansuelsmth@gmail.comSigned-off-by: Bjorn Andersson <andersson@kernel.org>

arch/arm64/boot/dts/qcom/ipq8074.dtsi

@@ -252,6 +252,8 @@ mdio: mdio@90000 {
 			clocks = <&gcc GCC_MDIO_AHB_CLK>;
 			clock-names = "gcc_mdio_ahb_clk";
 
+			clock-frequency = <6250000>;
+
 			status = "disabled";
 		};