riscv: dts: sophgo: add device tree for LicheeRV Nano

Import a slightly modified version of the LicheeRV Nano and SG2002
device trees from the Linux Kernel. The current supported IPs are UART,
MMC, Timer, PLIC and CLINT.

Signed-off-by: Thomas Bonnefille <thomas.bonnefille@bootlin.com>
diff --git a/arch/riscv/dts/sg2002-licheerv-nano-b.dts b/arch/riscv/dts/sg2002-licheerv-nano-b.dts
new file mode 100644
index 0000000..9871a75
--- /dev/null
+++ b/arch/riscv/dts/sg2002-licheerv-nano-b.dts
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Copyright (C) 2024 Thomas Bonnefille <thomas.bonnefille@bootlin.com>
+ */
+
+/dts-v1/;
+
+#include "sg2002.dtsi"
+
+/ {
+	model = "LicheeRV Nano B";
+	compatible = "sipeed,licheerv-nano-b", "sipeed,licheerv-nano", "sophgo,sg2002";
+
+	aliases {
+		gpio0 = &gpio0;
+		gpio1 = &gpio1;
+		gpio2 = &gpio2;
+		gpio3 = &gpio3;
+		serial0 = &uart0;
+		serial1 = &uart1;
+		serial2 = &uart2;
+		serial3 = &uart3;
+		serial4 = &uart4;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+};
+
+&osc {
+	clock-frequency = <25000000>;
+};
+
+&sdhci0 {
+	status = "okay";
+	bus-width = <4>;
+	no-1-8-v;
+	no-mmc;
+	no-sdio;
+};
+
+&uart0 {
+	status = "okay";
+};