soc: mediatek: mtk-dvfsrc: Add and propagate DVFSRC bandwidth type

soc: mediatek: mtk-dvfsrc: Add and propagate DVFSRC bandwidth type

In preparation for adding support for DVFSRC Version 4, add a new
mtk_dvfsrc_bw_type enumeration, and propagate it from specific bw
setting callbacks to __dvfsrc_set_dram_bw_v1(), which will use it
to choose calculation multipliers and dividers in v4 callbacks.

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