ASoC: Add missing gpio_free(S3C64XX_GPK(12)) in smartq_exit()

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Jassi Brar <jassi.brar@samsung.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/samsung/smartq_wm8987.c

@@ -274,6 +274,7 @@ err_unregister_device:
 
 static void __exit smartq_exit(void)
 {
+	gpio_free(S3C64XX_GPK(12));
 	snd_soc_jack_free_gpios(&smartq_jack, ARRAY_SIZE(smartq_jack_gpios),
 				smartq_jack_gpios);