arm64: dts: marvell: armada-3720-db: enable second UART port

Enable Armada-3720-DB second UART port by adding the corresponding
device tree node in the board DTS and enabling it.
Signed-off-by: Miquel Raynal <miquel.raynal@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>

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

@@ -227,7 +227,7 @@ partition@210000 {
 
 /*
  * Exported on the micro USB connector CON30(V2.0)/CON32(V1.4) through
- * an FTDI
+ * an FTDI (also on CON24(V2.0)/CON26(V1.4)).
  */
 &uart0 {
 	pinctrl-names = "default";
@@ -235,6 +235,13 @@ &uart0 {
 	status = "okay";
 };
 
+/* CON26(V2.0)/CON28(V1.4) */
+&uart1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart2_pins>;
+	status = "okay";
+};
+
 /* CON27(V2.0)/CON29(V1.4) */
 &usb2 {
 	status = "okay";