clk: mediatek: mt8365: convert to struct mtk_parent

clk: mediatek: mt8365: convert to struct mtk_parent

Convert all parent clock arrays to use struct mtk_parent. This will
allow us to simplify core code later by having only one possible data
type for mux parent arrays.

Reviewed-by: Macpaul Lin <macpaul.lin@mediatek.com>
Reviewed-by: Julien Stephan <jstephan@baylibre.com>
Link: https://patch.msgid.link/20260317-clk-mtk-unify-mux-parents-v3-10-a4760f5b0a80@baylibre.com
Signed-off-by: David Lechner <dlechner@baylibre.com>