soc: rockchip: grf: Set RK3128's vpu main clock

soc: rockchip: grf: Set RK3128's vpu main clock

RK3128 has a setting in GRF which selects whether the vpu attached iommu
uses the AXI clock of the decoder (vdpu) or the encoder (vepu). The
default is vepu but some part of the vendor firmware sets it to vdpu.

In order to be independent on whether any of those vendor firmware blobs is
used to boot the SoC reset "vpu main clock" setting to it's default value.

Signed-off-by: Alex Bee <knaerzche@gmail.com>
Link: https://lore.kernel.org/r/20240523185633.71355-3-knaerzche@gmail.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>