Display Port monitor could support kinds of mode which indicate
in monitor edid, not just one single display resolution which
defined in panel or devivetree property display timing.

Note: Gustavo Padovan try to remove the controller and phy
power on function in bind time at bellow commit:
	drm/exynos: do not start enabling DP at bind() phase

But for now driver need to read edid message in .get_modes()
function, so controller must be inited in bind time, so we
need to add controller init back.
Tested-by: Caesar Wang <wxt@rock-chips.com>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Yakir Yang <ykk@rock-chips.com>