iio: adc: at91-sama5d2_adc: use sysfs_emit() to instead of scnprintf()

Replace the open-code with sysfs_emit() to simplify the code.

Signed-off-by: ye xingchen <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/adc/at91-sama5d2_adc.c

···
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct at91_adc_state *st = iio_priv(indio_dev);
 
-	return scnprintf(buf, PAGE_SIZE, "%d\n", !!st->dma_st.dma_chan);
+	return sysfs_emit(buf, "%d\n", !!st->dma_st.dma_chan);
 }
 
 static ssize_t at91_adc_get_watermark(struct device *dev,
···
 	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
 	struct at91_adc_state *st = iio_priv(indio_dev);
 
-	return scnprintf(buf, PAGE_SIZE, "%d\n", st->dma_st.watermark);
+	return sysfs_emit(buf, "%d\n", st->dma_st.watermark);
 }
 
 static IIO_DEVICE_ATTR(hwfifo_enabled, 0444,