ARM: dts: at91: usb_a9g20: fix rtc node

The rv3029 compatible is missing its vendor string, add it.
Also fix the node name to be a proper generic name.
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

arch/arm/boot/dts/usb_a9g20_common.dtsi

@@ -20,8 +20,8 @@ memory {
 	};
 
 	i2c-gpio-0 {
-		rv3029c2@56 {
-			compatible = "rv3029c2";
+		rtc@56 {
+			compatible = "microcrystal,rv3029";
 			reg = <0x56>;
 		};
 	};