iio: inkern: add a missing space before if

This fixes the error reported by checkpatch.pl:

ERROR: space required before the open parenthesis '('
Signed-off-by: Slawomir Stepien <sst@poczta.fm>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/inkern.c

@@ -452,7 +452,7 @@ static int iio_channel_read(struct iio_channel *chan, int *val, int *val2,
 	if (val2 == NULL)
 		val2 = &unused;
 
-	if(!iio_channel_has_info(chan->channel, info))
+	if (!iio_channel_has_info(chan->channel, info))
 		return -EINVAL;
 
 	if (chan->indio_dev->info->read_raw_multi) {