rockchip: rk356x: Migrate to OF_UPSTREAM

Migrate RK356x boards that exists in Linux v6.8 to use OF_UPSTREAM.

Following targets is not migrated to use OF_UPSTREAM:
- anbernic-rgxx3-rk3566: Multi device target
- generic-rk3568: Generic target only meant for U-Boot use
- pinetab2-rk3566: Merged in v6.9-rc1

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>