ARM: dts: rockchip: Add rv1126 PD_VO entry

PD_VO power-domain tree diagram in RV1126 is connected to
- BIU_VO
- VOP
- RGA
- IEP
- DSIHOST

Add PD_VO power-domain entry in RV1126.

Signed-off-by: Jagan Teki <jagan@edgeble.ai>
Link: https://lore.kernel.org/r/20230731110012.2913742-10-jagan@edgeble.ai


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