rockchip: configs: puma-rk3399: disable VIDEO support that breaks Linux

rockchip: configs: puma-rk3399: disable VIDEO support that breaks Linux

RK3399 Puma has support for driving multiple displays at the same time,
the most notable scenario being HDMI+DSI since there exists a devkit
with both DSI display and HDMI output.

While HDMI seems to work fine in U-Boot, as the U-Boot logo is shown
whenever the EFI bootmeth is used, it messes up DSI in HDMI+DSI setup in
the Linux kernel. There are some ways to work around this bug but no
known appropriate fix for now, so let's rather not trigger this bug.

Since there isn't any client of ours that seems to be using this
feature, let's disable it for now. Users can re-enable this feature in
the event they have HDMI-only products.

Signed-off-by: Quentin Schulz <quentin.schulz@cherry.de>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>