rockchip: correctly set vop0 or vop1

The EDP_LCDC_SEL bit has to be set correctly to select vop0 or
vop1, but so far we have set it in both conditions, which is not
correct.

Can someone verify this is the correct way round?  vop1 -> set,
vop0 -> clear?

Signed-off-by: Patrick Wildt <patrick@blueri.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>