mfd: davinci_voicecodec: Tidyup header difinitions

mach/hardware.h is needed on C source code side, not header.
And struct davinci_vc is duplicated definition.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/davinci_voicecodec.c b/drivers/mfd/davinci_voicecodec.c
index dff2f19..4d0a5f3 100644
--- a/drivers/mfd/davinci_voicecodec.c
+++ b/drivers/mfd/davinci_voicecodec.c
@@ -32,6 +32,7 @@
 #include <sound/pcm.h>
 
 #include <linux/mfd/davinci_voicecodec.h>
+#include <mach/hardware.h>
 
 static const struct regmap_config davinci_vc_regmap = {
 	.reg_bits = 32,