ASoC: renesas: fsi: add fsi_clk_prepare/unprepare()

ASoC: renesas: fsi: add fsi_clk_prepare/unprepare()

Add fsi_clk_prepare() and fsi_clk_unprepare() helpers and call them
from fsi_dai_startup() and fsi_dai_shutdown().
This ensures clk_prepare() and clk_unprepare() are executed from
sleepable contexts and keeps clocks prepared only while audio streams
are active.

Acked-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Suggested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: bui duc phuc <phucduc.bui@gmail.com>
Link: https://patch.msgid.link/20260609113836.45079-11-phucduc.bui@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>