ARM: dts: exynos: Properly override node to use MDMA0 on Universal C210

The Universal C210 (Exynos4210) uses the secure interface of MDMA0,
instead of regular one - non-secure MDMA1.  DTS was overriding MDMA1
node address which caused DTC W=1 warning:

    arch/arm/boot/dts/exynos4.dtsi:707.25-716.6:
        Warning (simple_bus_reg): /soc/amba/mdma@12850000: simple-bus unit address format error, expected "12840000"

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>

arch/arm/boot/dts/exynos4.dtsi

@@ -675,7 +675,7 @@
 			status = "disabled";
 		};
 
-		amba {
+		amba: amba {
 			#address-cells = <1>;
 			#size-cells = <1>;
 			compatible = "simple-bus";

arch/arm/boot/dts/exynos4210-universal_c210.dts

@@ -177,6 +177,20 @@
 	};
 };
 
+&amba {
+	mdma0: mdma@12840000 {
+		compatible = "arm,pl330", "arm,primecell";
+		reg = <0x12840000 0x1000>;
+		interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&clock CLK_MDMA>;
+		clock-names = "apb_pclk";
+		#dma-cells = <1>;
+		#dma-channels = <8>;
+		#dma-requests = <1>;
+		power-domains = <&pd_lcd0>;
+	};
+};
+
 &camera {
 	status = "okay";
 
@@ -491,7 +505,8 @@
 };
 
 &mdma1 {
-	reg = <0x12840000 0x1000>;
+	/* Use the secure mdma0 */
+	status = "disabled";
 };
 
 &mixer {