iio: trigger: stm32-timer: fix write_raw return value

Fixes: 4adec7d ("iio: stm32 trigger: Add quadrature encoder device")

IIO core expects zero as return value for write_raw() callback
in case of success.

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@st.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/trigger/stm32-timer-trigger.c

@@ -406,9 +406,8 @@ static int stm32_counter_write_raw(struct iio_dev *indio_dev,
 
 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
-		regmap_write(priv->regmap, TIM_CNT, val);
+		return regmap_write(priv->regmap, TIM_CNT, val);
 
-		return IIO_VAL_INT;
 	case IIO_CHAN_INFO_SCALE:
 		/* fixed scale */
 		return -EINVAL;