drm/exynos/hdmi: code cleanup

The patch performs following clean-ups:
- remove unnecessary white spaces,
- remove obvious comments,
- fix tabulations,
- remove NULL initializators,
- re-order driver data.

The patch does not change driver's behavior.

Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>