clk: mediatek: Kconfig: Allow module build for core mt8192 clocks

Bootloaders must in a way setup the SoC to boot Linux: this means
that it will be possible to decompress a ramdisk and eventually
insert the core clock driver module from there.
Allow module build for all MT8192 clocks by switching to tristate.

Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Miles Chen <miles.chen@mediatek.com>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>
Link: https://lore.kernel.org/r/20230306140543.1813621-49-angelogioacchino.delregno@collabora.com


Signed-off-by: Stephen Boyd <sboyd@kernel.org>