dt-bindings: display: vop2: describe constraint SoC by SoC

As more SoCs variants are introduced, each SoC brings its own
unique set of constraints, describe this constraints SoC by
SoC will make things easier.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20250303034436.192400-5-andyshrk@163.com