soc: mediatek: mtk-dvfsrc: Add support for DVFSRCv4 and MT8196

soc: mediatek: mtk-dvfsrc: Add support for DVFSRCv4 and MT8196

Add support for the DVFSRC Version 4 by adding new functions for
vcore/dram levels (in v4, called gears instead), and for readout
of pre-programmed dvfsrc_opp entries, corresponding to each gear.

In the probe function, for v4, the curr_opps is initialized from
the get_hw_opps() function instead of platform data.

In order to make use of the new DVFSRCv4 code, also add support
for the MediaTek MT8196 SoC.

Co-developed-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>