arm64: dts: rockchip: add missing pmic information on Qnap-TS433

Fill in the missing pieces for RK809 pmic used on the TS433.

The regulator setup comes from the vendor-devicetree, so without proper
schematics its accuracy is somewhat unclear, but it looks really similar
to all the other rk3568 boards, so follows the reference design it seems.

The one caveat is related to vcc3v3_sd. This regulator needs to stay on.
When turned off because of no users, access to both PCIe controllers
will stall. Maybe this rail does supply the 100MHz refclk generation
or so.

Tested-by: Uwe Kleine-König <ukleinek@debian.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://lore.kernel.org/r/20240723195538.1133436-13-heiko@sntech.de