ASoC: cs35l32: remove second linux/slab.h inclusion

linux/slab.h was included twice.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Acked-by: Brian Austin <brian.austin@cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/codecs/cs35l32.c b/sound/soc/codecs/cs35l32.c
index 76f628b..c125925 100644
--- a/sound/soc/codecs/cs35l32.c
+++ b/sound/soc/codecs/cs35l32.c
@@ -25,7 +25,6 @@
 #include <linux/regulator/consumer.h>
 #include <linux/gpio/consumer.h>
 #include <linux/of_device.h>
-#include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>