arm64: allwinner: a64: add dma controller references to spi nodes

The spi controller nodes omit the dma controller/channel references, add
it.

This does not yet enable DMA for SPI transfers, as the spi-sun6i driver
lacks support for DMA, but always uses PIO to the FIFO.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>

arch/arm64/boot/dts/allwinner/sun50i-a64.dtsi

@@ -477,6 +477,8 @@ spi0: spi@1c68000 {
 			interrupts = <GIC_SPI 65 IRQ_TYPE_LEVEL_HIGH>;
 			clocks = <&ccu CLK_BUS_SPI0>, <&ccu CLK_SPI0>;
 			clock-names = "ahb", "mod";
+			dmas = <&dma 23>, <&dma 23>;
+			dma-names = "rx", "tx";
 			pinctrl-names = "default";
 			pinctrl-0 = <&spi0_pins>;
 			resets = <&ccu RST_BUS_SPI0>;
@@ -492,6 +494,8 @@ spi1: spi@1c69000 {
 			interrupts = <GIC_SPI 66 IRQ_TYPE_LEVEL_HIGH>;
 			clocks = <&ccu CLK_BUS_SPI1>, <&ccu CLK_SPI1>;
 			clock-names = "ahb", "mod";
+			dmas = <&dma 24>, <&dma 24>;
+			dma-names = "rx", "tx";
 			pinctrl-names = "default";
 			pinctrl-0 = <&spi1_pins>;
 			resets = <&ccu RST_BUS_SPI1>;