clk: mediatek: Add new clock driver to handle FHCTL hardware

clk: mediatek: Add new clock driver to handle FHCTL hardware

To implement frequency hopping and spread spectrum clocking
function, we introduce new clock type and APIs to handle
FHCTL hardware.

Co-developed-by: Edward-JW Yang <edward-jw.yang@mediatek.com>
Signed-off-by: Edward-JW Yang <edward-jw.yang@mediatek.com>
Signed-off-by: Johnson Wang <johnson.wang@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20221121122957.21611-4-johnson.wang@mediatek.com
Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>