mfd: lp873x: Remove unused mutex lock from struct lp873x

The mutex is not used, so remove it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/lp873x.c b/drivers/mfd/lp873x.c
index 9af064c..873c608 100644
--- a/drivers/mfd/lp873x.c
+++ b/drivers/mfd/lp873x.c
@@ -53,8 +53,6 @@
 		return ret;
 	}
 
-	mutex_init(&lp873->lock);
-
 	ret = regmap_read(lp873->regmap, LP873X_REG_OTP_REV, &otpid);
 	if (ret) {
 		dev_err(lp873->dev, "Failed to read OTP ID\n");
diff --git a/include/linux/mfd/lp873x.h b/include/linux/mfd/lp873x.h
index 83b1bd7..edbec83 100644
--- a/include/linux/mfd/lp873x.h
+++ b/include/linux/mfd/lp873x.h
@@ -263,7 +263,6 @@
 struct lp873x {
 	struct device *dev;
 	u8 rev;
-	struct mutex lock;	/* lock guarding the data structure */
 	struct regmap *regmap;
 };
 #endif /* __LINUX_MFD_LP873X_H */