regulator: wm831x-ldo: Check return value of wm831x_reg_read()

wm831x_reg_read() returns negative error code on failure.
This prevents using the error code as the value read.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

drivers/regulator/wm831x-ldo.c

@@ -205,6 +205,8 @@ static int wm831x_gp_ldo_get_status(struct regulator_dev *rdev)
 
 	/* Is it reporting under voltage? */
 	ret = wm831x_reg_read(wm831x, WM831X_LDO_UV_STATUS);
+	if (ret < 0)
+		return ret;
 	if (ret & mask)
 		return REGULATOR_STATUS_ERROR;
 
@@ -469,6 +471,8 @@ static int wm831x_aldo_get_status(struct regulator_dev *rdev)
 
 	/* Is it reporting under voltage? */
 	ret = wm831x_reg_read(wm831x, WM831X_LDO_UV_STATUS);
+	if (ret < 0)
+		return ret;
 	if (ret & mask)
 		return REGULATOR_STATUS_ERROR;