ASoC: Make pmdown_time a long

Fixes a warning.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
diff --git a/include/sound/soc.h b/include/sound/soc.h
index d9d88dd..5d234a8 100644
--- a/include/sound/soc.h
+++ b/include/sound/soc.h
@@ -521,7 +521,7 @@
 	int (*set_bias_level)(struct snd_soc_card *,
 			      enum snd_soc_bias_level level);
 
-	int pmdown_time;
+	long pmdown_time;
 
 	/* CPU <--> Codec DAI links  */
 	struct snd_soc_dai_link *dai_link;