ASoC: atmel: mchp-pdmc: Use snd_ctl_remove_id()

Use the standard snd_ctl_remove_id() helper instead of open code for
removing a kctl.  This helps for avoiding possible races.

Reviewed-by: Claudiu Beznea <claudiu.beznea@tuxon.dev>
Acked-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230718141304.1032-4-tiwai@suse.de


Signed-off-by: Takashi Iwai <tiwai@suse.de>