OMAPDSS: TPO-TD03MTEA1: add set/check timing functions

On pandora we use .set_timings to alter refresh rate,
so add .check_timings/.set_timings functions.

Signed-off-by: Grazvydas Ignotas <notasas@gmail.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>