clk: mediatek: Split MT8195 clock drivers and allow module build

clk: mediatek: Split MT8195 clock drivers and allow module build

MT8195 clock drivers were encapsulated in one single (and big) Kconfig
option: there's no reason to do that, as it is totally unnecessary to
build in all or none of them.

Split them out: keep boot-critical clocks as bool and allow choosing
non critical clocks as tristate.

As a note, the dependencies of VDEC/VENCSYS and CAM/IMG/IPE/WPESYS
are not for build-time but rather for runtime, as clocks registered
by those have runtime dependencies on either or both VPP and IMGSYS.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20230306140543.1813621-40-angelogioacchino.delregno@collabora.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>