arm64: dts: rockchip: Enable GPU on rk3566-pinenote

arm64: dts: rockchip: Enable GPU on rk3566-pinenote

The GPU is most useful when used together with the EBC on the PineNote,
which is not yet described. But there's no reason not to define the GPU
already as the hardware is present and could be used without the EBC.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Diederik de Haas <diederik@cknow-tech.com>
Link: https://patch.msgid.link/20260305120620.173600-1-diederik@cknow-tech.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>