iio: Don't compare boolean values to true/false

Fixes the following warnings from coccicheck:
	drivers/iio/inkern.c:81:6-14: WARNING: Comparison to bool
	drivers/iio/dac/ad5686.c:191:5-11: WARNING: Comparison to bool

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/dac/ad5686.c

@@ -188,7 +188,7 @@ static ssize_t ad5686_write_dac_powerdown(struct iio_dev *indio_dev,
 	if (ret)
 		return ret;
 
-	if (readin == true)
+	if (readin)
 		st->pwr_down_mask |= (0x3 << (chan->channel * 2));
 	else
 		st->pwr_down_mask &= ~(0x3 << (chan->channel * 2));

drivers/iio/inkern.c

@@ -78,7 +78,7 @@ int iio_map_array_unregister(struct iio_dev *indio_dev,
 				found_it = true;
 				break;
 			}
-		if (found_it == false) {
+		if (!found_it) {
 			ret = -ENODEV;
 			goto error_ret;
 		}