Enable the drm bridge pre_enable_prev_first flag so that the
previous bridge pre_enable should be called first before the
pre_enable for the tc358764 bridge is called.

This makes sure that the previous bridge should be initialized
properly before the tc358764 bridge is powered up.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Signed-off-by: Inki Dae <inki.dae@samsung.com>