riscv: dts: sifive unmatched: Add PWM controlled LEDs

This adds the two PWM controlled LEDs to the HiFive Unmatched device
tree. D12 is just a regular green diode, but D2 is an RGB diode with 3
PWM inputs controlling the three different colours.
Signed-off-by: Emil Renner Berthing <emil.renner.berthing@canonical.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Pavel Machek <pavel@ucw.cz>
Tested-by: Ron Economos <re@w6rz.net>
Link: https://lore.kernel.org/r/20220705210143.315151-5-emil.renner.berthing@canonical.comSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts

@@ -4,6 +4,8 @@
 #include "fu740-c000.dtsi"
 #include <dt-bindings/gpio/gpio.h>
 #include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/leds/common.h>
+#include <dt-bindings/pwm/pwm.h>
 
 /* Clock frequency (in Hz) of the PCB crystal for rtcclk */
 #define RTCCLK_FREQ		1000000
@@ -44,6 +46,46 @@ gpio-poweroff {
 		compatible = "gpio-poweroff";
 		gpios = <&gpio 2 GPIO_ACTIVE_LOW>;
 	};
+
+	led-controller-1 {
+		compatible = "pwm-leds";
+
+		led-d12 {
+			pwms = <&pwm0 0 7812500 PWM_POLARITY_INVERTED>;
+			active-low;
+			color = <LED_COLOR_ID_GREEN>;
+			max-brightness = <255>;
+			label = "d12";
+		};
+	};
+
+	led-controller-2 {
+		compatible = "pwm-leds-multicolor";
+
+		multi-led {
+			color = <LED_COLOR_ID_RGB>;
+			max-brightness = <255>;
+			label = "d2";
+
+			led-red {
+				pwms = <&pwm0 2 7812500 PWM_POLARITY_INVERTED>;
+				active-low;
+				color = <LED_COLOR_ID_RED>;
+			};
+
+			led-green {
+				pwms = <&pwm0 1 7812500 PWM_POLARITY_INVERTED>;
+				active-low;
+				color = <LED_COLOR_ID_GREEN>;
+			};
+
+			led-blue {
+				pwms = <&pwm0 3 7812500 PWM_POLARITY_INVERTED>;
+				active-low;
+				color = <LED_COLOR_ID_BLUE>;
+			};
+		};
+	};
 };
 
 &uart0 {