drm/exynos: Check g2d cmd list for g2d restrictions

drm/exynos: Check g2d cmd list for g2d restrictions

This patch checks command list from user for g2d restrictions.

For now, g2d driver wasn't considered for G2D hardware restrictions
properly. The below is the restrictions to G2D hardware and this patch
considers them.
    - width or height value in the command list
	has to be in valid range (1 to 8000 pixels)
    - The requested area should be less than buffer size.
    - right has to be bigger than left.
    - bottom has to be bigger than top.

Changelog v2:
- Fix merge conflict.

Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>