arm64: dts: rockchip: enable gpu on rk3588-tiger

Enable the mali gpu node and add the som-specific supply-regulator.

Signed-off-by: Heiko Stuebner <heiko.stuebner@cherry.de>
Reviewed-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Link: https://lore.kernel.org/r/20240327112120.1181570-2-heiko@sntech.de


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

[ upstream commit: f5256f8ed4b729c3ab9d9cd7d406313773484b59 ]

(cherry picked from commit 27350b241eafea37dc94743cd9c5dd83295faca9)