arm64: dts: rockchip: Add VEPU121 to RK3588

arm64: dts: rockchip: Add VEPU121 to RK3588

RK3588 has 4 Hantro G1 encoder-only cores. They are all independent IP,
but can be used as a cluster (i.e. sharing work between the cores).
These cores are called VEPU121 in the TRM. The TRM describes one more
VEPU121, but that is combined with a Hantro H1. That one will be handled
using the VPU binding instead.

Signed-off-by: Emmanuel Gil Peyrot <linkmauve@linkmauve.fr>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20240827181206.147617-2-sebastian.reichel@collabora.com
Signed-off-by: Heiko Stuebner <heiko@sntech.de>