apll2_d4, apll12_div4, top_a2sys and top_aud_iec are possibly used in
the future. To prevent from breaking binding ABI after any mt8188 dts
upstream, add these clocks to clock list in advance.

Signed-off-by: Trevor Wu <trevor.wu@mediatek.com
Link: https://lore.kernel.org/r/20230510035526.18137-8-trevor.wu@mediatek.com
Signed-off-by: Mark Brown <broonie@kernel.org