arm64: dts: ti: Add reserved memory for watchdog

This patch adds a reserved memory for the TI AM65X platform watchdog
to reserve the specific info, triggering the watchdog reset in last
boot, to know if the board reboot is due to a watchdog reset.
Signed-off-by: Li Hua Qian <huaqian.li@siemens.com>
Link: https://lore.kernel.org/r/20240117060654.109424-1-huaqian.li@siemens.comSigned-off-by: Vignesh Raghavendra <vigneshr@ti.com>

arch/arm64/boot/dts/ti/k3-am65-iot2050-common.dtsi

@@ -76,6 +76,12 @@ rtos_ipc_memory_region: ipc-memories@a2000000 {
 			alignment = <0x1000>;
 			no-map;
 		};
+
+		/* To reserve the power-on(PON) reason for watchdog reset */
+		wdt_reset_memory_region: wdt-memory@a2200000 {
+			reg = <0x00 0xa2200000 0x00 0x1000>;
+			no-map;
+		};
 	};
 
 	leds {
@@ -608,6 +614,10 @@ &mcu_r5fss0_core1 {
 	mboxes = <&mailbox0_cluster1 &mbox_mcu_r5fss0_core1>;
 };
 
+&mcu_rti1 {
+	memory-region = <&wdt_reset_memory_region>;
+};
+
 &icssg0_mdio {
 	status = "okay";
 	pinctrl-names = "default";