dt-bindings: clock: rk3588: add missing PCLK_VO1GRF

Add PCLK_VO1GRF to complement PCLK_VO0GRF. This will be needed
for HDMI support.

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20240126182919.48402-4-sebastian.reichel@collabora.com


Signed-off-by: Heiko Stuebner <heiko@sntech.de>