Staging: iio: Remove explicit comparison to NULL

This patch simplifies pointer comparison to NULL and makes code
easier to read. Warning found by checkpatch.pl.
Signed-off-by: Cristina Opriceana <cristina.opriceana@gmail.com>
Reviewed-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/iio/frequency/ad9832.c

@@ -220,7 +220,7 @@ static int ad9832_probe(struct spi_device *spi)
 	}
 
 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
-	if (indio_dev == NULL) {
+	if (!indio_dev) {
 		ret = -ENOMEM;
 		goto error_disable_reg;
 	}

drivers/staging/iio/frequency/ad9834.c

@@ -336,7 +336,7 @@ static int ad9834_probe(struct spi_device *spi)
 	}
 
 	indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
-	if (indio_dev == NULL) {
+	if (!indio_dev) {
 		ret = -ENOMEM;
 		goto error_disable_reg;
 	}