riscv: dts: andes: add Voyager board device tree

Introduce the device tree support for Voyager development board.

Currently only support booting into console with only uart,
other features will be added later.

Signed-off-by: Ben Zong-You Xie <ben717@andestech.com>
Link: https://lore.kernel.org/r/20250711133025.2192404-8-ben717@andestech.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/riscv/boot/dts/Makefile

@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 subdir-y += allwinner
+subdir-y += andes
 subdir-y += canaan
 subdir-y += microchip
 subdir-y += renesas

arch/riscv/boot/dts/andes/Makefile

@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+dtb-$(CONFIG_ARCH_ANDES) += qilai-voyager.dtb

arch/riscv/boot/dts/andes/qilai-voyager.dts

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Copyright (C) 2025 Andes Technology Corporation. All rights reserved.
+ */
+
+#include "qilai.dtsi"
+
+/ {
+	model = "Voyager";
+	compatible = "andestech,voyager", "andestech,qilai";
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@400000000 {
+		device_type = "memory";
+		reg = <0x4 0x00000000 0x4 0x00000000>;
+	};
+};
+
+&uart0 {
+	status = "okay";
+};