iio: sensors-core: st: Check st_sensors_set_drdy_int_pin()'s return value

Value from st_sensors_set_drdy_int_pin() is assigned to err here,
but that stored value is not used before it is overwritten.  To fix
this we're enforcing a check on st_sensors_set_drdy_int_pin()'s
return value and if it's an error, we're returning right away.

Cc: jic23@kernel.org
Cc: linux-iio@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/iio/common/st_sensors/st_sensors_core.c

@@ -306,8 +306,11 @@ int st_sensors_init_sensor(struct iio_dev *indio_dev,
 	if (of_pdata)
 		pdata = of_pdata;
 
-	if (pdata)
+	if (pdata) {
 		err = st_sensors_set_drdy_int_pin(indio_dev, pdata);
+		if (err < 0)
+			return err;
+	}
 
 	err = st_sensors_set_enable(indio_dev, false);
 	if (err < 0)