ARM: dts: exynos: Enable the HDMI CEC device on Exynos4412 Odroid boards

Add a dts node entry and enable the HDMI CEC device present in the Exynos4
family of SoCs.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
[k.kozlowski: Put the node in alphabetical order]
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>