ARM: dts: microchip: sama7d65: add dma properties to usart6

Add the dma property and associated dma activation for usart6 as part of
flx6 node.
Is useful for usual default console on this product.

Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
Link: https://lore.kernel.org/r/20260102170135.70717-4-nicolas.ferre@microchip.com
Signed-off-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>

Author: noglitch

arch/arm/boot/dts/microchip/sama7d65.dtsi

@@ -617,6 +617,11 @@
 				interrupts = <GIC_SPI 40 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&pmc PMC_TYPE_PERIPHERAL 40>;
 				clock-names = "usart";
+				dmas = <&dma1 AT91_XDMAC_DT_PERID(18)>,
+				       <&dma1 AT91_XDMAC_DT_PERID(17)>;
+				dma-names = "tx", "rx";
+				atmel,use-dma-rx;
+				atmel,use-dma-tx;
 				atmel,usart-mode = <AT91_USART_MODE_SERIAL>;
 				atmel,fifo-size = <32>;
 				status = "disabled";