drm/exynos: fix unnecessary resource cleanup

This patch removes unnecessary drm_mode_config_cleanup call.

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

diff --cc drivers/gpu/drm/exynos/exynos_drm_drv.c
Simple merge