ARM: dts: at91: Enable DMA on sama5d2_xplained console

Enable DMA on uart1 to get a more reliable console.

Cc: stable <stable@vger.kernel.org> #v4.3+
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>

arch/arm/boot/dts/at91-sama5d2_xplained.dts

@@ -148,6 +148,8 @@ pdmic@f8018000 {
 			uart1: serial@f8020000 {
 				pinctrl-names = "default";
 				pinctrl-0 = <&pinctrl_uart1_default>;
+				atmel,use-dma-rx;
+				atmel,use-dma-tx;
 				status = "okay";
 			};