ARM: dts: add hdmi related nodes for exynos4 SoCs

This patch adds entries for HDMI, Mixer and i2c with hdmi-phy modules
found in Exynos 4210 and 4x12 SoCs.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>