powerpc/83xx: add DMA controller to mpc8308 device-tree node

MPC8308 has DMA controller compatible with mpc512x_dma driver. This
patch adds device-tree node to support DMA controller on MPC8308RDB
board.
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Acked-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

arch/powerpc/boot/dts/mpc8308rdb.dts

@@ -265,6 +265,14 @@ ipic-msi@7c0 {
 			interrupt-parent = < &ipic >;
 		};
 
+		dma@2c000 {
+			compatible = "fsl,mpc8308-dma", "fsl,mpc5121-dma";
+			reg = <0x2c000 0x1800>;
+			interrupts = <3 0x8
+					94 0x8>;
+			interrupt-parent = < &ipic >;
+		};
+
 	};
 
 	pci0: pcie@e0009000 {