ARM: at91/dt: Add Acme Arietta G25

Add a minimum Device Tree for Acme Arietta G25.
http://acme.systems/arietta

Signed-off-by: Alexandre Belloni <[e-mail]>
Acked-by: Sergio Tanzilli <[e-mail]>
Signed-off-by: Nicolas Ferre <[e-mail]>

arch/arm/boot/dts/Makefile

···
 	at91sam9n12ek.dtb \
 	at91sam9rlek.dtb \
 	at91-ariag25.dtb \
+	at91-ariettag25.dtb \
 	at91-cosino_mega2560.dtb \
 	at91-kizboxmini.dtb \
 	at91sam9g15ek.dtb \

arch/arm/boot/dts/at91-ariettag25.dts

···
+/*
+ * Device Tree file for Arietta G25
+ * This device tree is minimal, to activate more peripherals, see:
+ * http://dts.acmesystems.it/arietta/
+ */
+/dts-v1/;
+#include "at91sam9g25.dtsi"
+/ {
+	model = "Acme Systems Arietta G25";
+	compatible = "acme,ariettag25", "atmel,at91sam9x5", "atmel,at91sam9";
+
+	aliases {
+		serial0 = &dbgu;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory {
+		reg = <0x20000000 0x8000000>;
+	};
+
+	clocks {
+		slow_xtal {
+			clock-frequency = <32768>;
+		};
+
+		main_xtal {
+			clock-frequency = <12000000>;
+		};
+	};
+
+	ahb {
+		apb {
+			mmc0: mmc@f0008000 {
+				pinctrl-0 = <
+				  &pinctrl_mmc0_slot0_clk_cmd_dat0
+				  &pinctrl_mmc0_slot0_dat1_3>;
+				status = "okay";
+
+				slot@0 {
+					reg = <0>;
+					bus-width = <4>;
+				};
+			};
+
+			usb2: gadget@f803c000 {
+				status = "okay";
+			};
+
+			dbgu: serial@fffff200 {
+				status = "okay";
+			};
+
+			rtc@fffffeb0 {
+				status = "okay";
+			};
+		};
+
+		usb0: ohci@00600000 {
+			status = "okay";
+			num-ports = <3>;
+		};
+
+		usb1: ehci@00700000 {
+			status = "okay";
+		};
+	};
+
+	leds {
+		compatible = "gpio-leds";
+		arietta_led {
+			label = "arietta_led";
+			gpios = <&pioB 8 GPIO_ACTIVE_HIGH>; /* PB8 */
+			linux,default-trigger = "heartbeat";
+		};
+	};
+};