ARM: dts: Use labels for overriding nodes in exynos4412-odroid

Usage of labels instead of full paths reduces possible mistakes when
overriding nodes.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>

For thermal zones:
Acked-by: Eduardo Valentin <edubezval@gmail.com>

Signed-off-by: Kukjin Kim <kgene@kernel.org>