ARM: dts: exynos: Enable UART3 on Exynos5410

Just like other Exynos5 family SoCs, this one has four UARTs. Configure
clocks for UART3 and enable it.
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Reviewed-by: NJavier Martinez Canillas <javier@osg.samsung.com>

arch/arm/boot/dts/exynos5410.dtsi

@@ -218,7 +218,8 @@
 };
 
 &serial_3 {
-	status = "disabled";
+	clocks = <&clock CLK_UART3>, <&clock CLK_SCLK_UART3>;
+	clock-names = "uart", "clk_uart_baud0";
 };
 
 &sromc {