ASoC: Remove unneeded platform_device.h inclusions from CODECs

They've not been needed for a long time if they were ever required.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/wm8974.c

@@ -17,7 +17,6 @@
 #include <linux/delay.h>
 #include <linux/pm.h>
 #include <linux/i2c.h>
-#include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <sound/core.h>
 #include <sound/pcm.h>