video: Add an enum for active low/high
This is used for video signals in some drivers so provide a standard way
of representing it in an enum.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>