CHROMIUM: drm/exynos: Pass drm_display_mode to exynos_panel_ops.mode_set

CHROMIUM: drm/exynos: Pass drm_display_mode to exynos_panel_ops.mode_set

Specifying the actual type is cleaner and lets the compiler type check
for us.  It will also make it possible to add some DRM_DEBUG messages
that access the mode object in the mode_set() handlers.

Signed-off-by: Daniel Kurtz <djkurtz@chromium.org>
BUG=chromium-os:36608
TEST=builds clean

Change-Id: Ida2149a2e1bf3a3c57b528350f36e31fef8f6b4d
Reviewed-on: https://gerrit.chromium.org/gerrit/38889
Commit-Ready: Daniel Kurtz <djkurtz@chromium.org>
Reviewed-by: Daniel Kurtz <djkurtz@chromium.org>
Tested-by: Daniel Kurtz <djkurtz@chromium.org>