drm/exynos: remove DRM_EXYNOS_DMABUF config

The exynos drm driver has DRIVER_PRIME capability, then it's reasonable
to support dmabuf as default. Remove DRM_EXYNOS_DMABUF config, it will
prevent that user selects the option unnecessarily.

Signed-off-by: Joonyoung Shim <jy0922.shim@samsung.com>
Reviewed-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Signed-off-by: Inki Dae <inki.dae@samsung.com>

drivers/gpu/drm/exynos/Kconfig

@@ -16,12 +16,6 @@ config DRM_EXYNOS_IOMMU
 	depends on DRM_EXYNOS && EXYNOS_IOMMU && ARM_DMA_USE_IOMMU
 	default y
 
-config DRM_EXYNOS_DMABUF
-	bool "EXYNOS DRM DMABUF"
-	depends on DRM_EXYNOS
-	help
-	  Choose this option if you want to use DMABUF feature for DRM.
-
 config DRM_EXYNOS_FIMD
 	bool "Exynos DRM FIMD"
 	depends on DRM_EXYNOS && !FB_S3C