drm/exynos: hdmi: remove unnecessary dedicated i2c drivers

The i2c drivers for ddc and hdmiphy are already removed from build
and instead, i2c clients registered via devicetree are used. So this
patch removes the unnecessary i2c drivers.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>