regulator: max8952: removed unused mutex.

This patch removes a mutex that is never used in the driver.

Reported-by: Axel Lin
Signed-off-by: MyungJoo Ham <[e-mail]>
Acked-by: Mark Brown <[e-mail]>
Signed-off-by: Liam Girdwood <[e-mail]>

drivers/regulator/max8952.c

···
 #include <linux/platform_device.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/max8952.h>
-#include <linux/mutex.h>
 #include <linux/gpio.h>
 #include <linux/io.h>
 #include <linux/slab.h>
···
 struct max8952_data {
 	struct i2c_client	*client;
 	struct device		*dev;
-	struct mutex		mutex;
 	struct max8952_platform_data *pdata;
 	struct regulator_dev	*rdev;
 
···
 	max8952->client = client;
 	max8952->dev = &client->dev;
 	max8952->pdata = pdata;
-	mutex_init(&max8952->mutex);
 
 	max8952->rdev = regulator_register(&regulator, max8952->dev,
 			&pdata->reg_data, max8952);