arm64: dts: ti: k3-am642-evm: Describe main_uart1 pins

Describe the main_uart1 pins even though it is a reserved node for
hardware complete description. This is used by other users of device
tree to help configure the SoC per board requirements.
Signed-off-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Roger Quadros <rogerq@kernel.org>
Link: https://lore.kernel.org/r/20230414073328.381336-8-nm@ti.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/k3-am642-evm.dts

@@ -215,6 +215,15 @@ AM64X_IOPAD(0x0290, PIN_INPUT, 0) /* MMC1_CLKLB */
 		>;
 	};
 
+	main_uart1_pins_default: main-uart1-pins-default {
+		pinctrl-single,pins = <
+			AM64X_IOPAD(0x0248, PIN_INPUT, 0)		/* (D16) UART1_CTSn */
+			AM64X_IOPAD(0x024c, PIN_OUTPUT, 0)		/* (E16) UART1_RTSn */
+			AM64X_IOPAD(0x0240, PIN_INPUT, 0)		/* (E15) UART1_RXD */
+			AM64X_IOPAD(0x0244, PIN_OUTPUT, 0)		/* (E14) UART1_TXD */
+		>;
+	};
+
 	main_uart0_pins_default: main-uart0-pins-default {
 		pinctrl-single,pins = <
 			AM64X_IOPAD(0x0238, PIN_INPUT, 0) /* (B16) UART0_CTSn */
@@ -340,6 +349,8 @@ &main_uart0 {
 /* main_uart1 is reserved for firmware usage */
 &main_uart1 {
 	status = "reserved";
+	pinctrl-names = "default";
+	pinctrl-0 = <&main_uart1_pins_default>;
 };
 
 &main_i2c0 {