arm64: dts: marvell: eDPU: drop redundant address/size-cells

The ethernet-switch node does not have children with unit addresses, so
address/size-cells are not really correct, as reported by dtc W=1
warning:

  armada-3720-eDPU.dts:26.19-60.4: Warning (avoid_unnecessary_addr_size): /soc/internal-regs@d0000000/mdio@32004/switch@0: unnecessary #address-cells/#size-cells without "ranges" or child "reg" property

This probably also fixes dtbs_check warning, but I could not find it, so
not sure about that.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>

arch/arm64/boot/dts/marvell/armada-3720-eDPU.dts

@@ -25,8 +25,6 @@ &mdio {
 	/* Actual device is MV88E6361 */
 	switch: switch@0 {
 		compatible = "marvell,mv88e6190";
-		#address-cells = <1>;
-		#size-cells = <0>;
 		reg = <0>;
 		status = "disabled";