ARM: dts: bcm2835: adjust DMA node names

After converting the bcm2835-dma DT binding to YAML, the DT schema
checks gave warnings like:

$nodename:0: 'dma@7e007000' does not match '^dma-controller(@.*)?$'

So fix them accordingly.
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/20230617133620.53129-4-stefan.wahren@i2se.comSigned-off-by: Florian Fainelli <florian.fainelli@broadcom.com>

arch/arm/boot/dts/broadcom/bcm2711.dtsi

@@ -76,7 +76,7 @@ thermal: thermal {
 			};
 		};
 
-		dma: dma@7e007000 {
+		dma: dma-controller@7e007000 {
 			compatible = "brcm,bcm2835-dma";
 			reg = <0x7e007000 0xb00>;
 			interrupts = <GIC_SPI 80 IRQ_TYPE_LEVEL_HIGH>,

arch/arm/boot/dts/broadcom/bcm2835-common.dtsi

@@ -8,7 +8,7 @@ / {
 	interrupt-parent = <&intc>;
 
 	soc {
-		dma: dma@7e007000 {
+		dma: dma-controller@7e007000 {
 			compatible = "brcm,bcm2835-dma";
 			reg = <0x7e007000 0xf00>;
 			interrupts = <1 16>,