iio: core: Use __sysfs_match_string() helper

Use __sysfs_match_string() helper instead of open coded variant.

Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/industrialio-core.c

@@ -478,21 +478,16 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
 	size_t len)
 {
 	const struct iio_enum *e = (const struct iio_enum *)priv;
-	unsigned int i;
 	int ret;
 
 	if (!e->set)
 		return -EINVAL;
 
-	for (i = 0; i < e->num_items; i++) {
-		if (sysfs_streq(buf, e->items[i]))
-			break;
-	}
-
-	if (i == e->num_items)
-		return -EINVAL;
+	ret = __sysfs_match_string(e->items, e->num_items, buf);
+	if (ret < 0)
+		return ret;
 
-	ret = e->set(indio_dev, chan, i);
+	ret = e->set(indio_dev, chan, ret);
 	return ret ? ret : len;
 }
 EXPORT_SYMBOL_GPL(iio_enum_write);