ASoC: renesas: rz-ssi: Rely on the ASoC subsystem to runtime resume/suspend the SSI

The ASoC subsystem takes care of runtime resume/suspend the audio
devices when needed. Just enable the runtime PM on the SSI driver and
let the subsystem runtime resume/suspend it. While at it use directly
the devm_pm_runtime_enable().

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Link: https://patch.msgid.link/20241210170953.2936724-14-claudiu.beznea.uj@bp.renesas.com


Signed-off-by: Mark Brown <broonie@kernel.org>