ASoC: ad1938: fix typo, rename mask to rx_mask for ad1938_set_tdm_slot

Signed-off-by: Barry Song <21cnbao@gmail.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/sound/soc/codecs/ad1938.c b/sound/soc/codecs/ad1938.c
index 5d48918..735c356 100644
--- a/sound/soc/codecs/ad1938.c
+++ b/sound/soc/codecs/ad1938.c
@@ -145,7 +145,7 @@
 }
 
 static int ad1938_set_tdm_slot(struct snd_soc_dai *dai, unsigned int tx_mask,
-			       unsigned int mask, int slots, int width)
+			       unsigned int rx_mask, int slots, int width)
 {
 	struct snd_soc_codec *codec = dai->codec;
 	int dac_reg = codec->read(codec, AD1938_DAC_CTRL1);