exynos: Added exynos specific DRM test

Added exynosdrmtest, a exynos specific DRM test which will be
used for testing the direct IOCTLs to exynos gem module as well
as test the exynos drm prime module for importing and exporting
gem objects to fd.

BUG=None
TEST=Tested with DRM application - exynosdrmtest

Signed-off-by: Prathyush K <prathyush.k@samsung.com>
Change-Id: Ia384542adda22d562573e080d8383f2b011922c4
Reviewed-on: https://gerrit.chromium.org/gerrit/22141
Commit-Ready: Anush Elangovan <anush@google.com>
Reviewed-by: Anush Elangovan <anush@google.com>
3 files changed