ARM: dts: Clean up indentation for exynos5410-smdk5410

The UART status properties are indented one level too deep, and we want
to derive a device tree for the ODROID-XU. Fix this before it propagates.

Signed-off-by: Andreas Faerber <afaerber@suse.de>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>