mfd: Remove unused max77693 iolock mutex

Now this driver is using regmap APIs, the iolock mutex is not used and can be
removed.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/max77693.c

@@ -138,8 +138,6 @@ static int max77693_i2c_probe(struct i2c_client *i2c,
 
 	max77693->wakeup = pdata->wakeup;
 
-	mutex_init(&max77693->iolock);
-
 	if (max77693_read_reg(max77693->regmap,
 				MAX77693_PMIC_REG_PMIC_ID2, &reg_data) < 0) {
 		dev_err(max77693->dev, "device not found on this channel\n");

include/linux/mfd/max77693-private.h

@@ -190,7 +190,6 @@ struct max77693_dev {
 	struct i2c_client *i2c;		/* 0xCC , PMIC, Charger, Flash LED */
 	struct i2c_client *muic;	/* 0x4A , MUIC */
 	struct i2c_client *haptic;	/* 0x90 , Haptic */
-	struct mutex iolock;
 
 	int type;