riscv: dts: spacemit: add gpio LED for system heartbeat

Leverage GPIO to support system LED to indicate activity of CPUs.

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Yixun Lan <[email protected]>

Author: dlan17

arch/riscv/boot/dts/spacemit/k1-bananapi-f3.dts

@@ -17,6 +17,17 @@
 	chosen {
 		stdout-path = "serial0";
 	};
+
+	leds {
+		compatible = "gpio-leds";
+
+		led1 {
+			label = "sys-led";
+			gpios = <&gpio K1_GPIO(96) GPIO_ACTIVE_HIGH>;
+			linux,default-trigger = "heartbeat";
+			default-state = "on";
+		};
+	};
 };
 
 &uart0 {