arm64: dts: rockchip: fix PCIe 3.3V regulator voltage on 9Tripod X3568 v4

arm64: dts: rockchip: fix PCIe 3.3V regulator voltage on 9Tripod X3568 v4

The regulator type is "regulator-fixed" since its voltage always be
3.3v, min and max should be 3300000 make the regulator has a voltage

The regulator is supplied by dc_12v, so add the vin-supply.

Link: https://github.com/rockchip-linux/kernel/commit/17e9559f67d26f3c602e38a24feb5194e51ac782
Signed-off-by: Coia Prant <coiaprant@gmail.com>
Link: https://patch.msgid.link/20251114092114.62664-2-coiaprant@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>