staging: iio: ad9834: fix chip name typo in comments

Two comments incorrectly refer to 'AD9843' instead of 'AD9834'.
Fix the copy-paste typo.

Signed-off-by: Angus Gardner <angusg778@gmail.com>
Reviewed-by: Maxwell Doose <m32285159@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

Author: Angus Gardner

drivers/staging/iio/frequency/ad9834.c

@@ -167,7 +167,7 @@ static ssize_t ad9834_write(struct device *dev,
 		break;
 	case AD9834_OPBITEN:
 		if (st->control & AD9834_MODE) {
-			ret = -EINVAL;  /* AD9843 reserved mode */
+			ret = -EINVAL;  /* AD9834 reserved mode */
 			break;
 		}
 
@@ -242,7 +242,7 @@ static ssize_t ad9834_store_wavetype(struct device *dev,
 				st->control &= ~AD9834_OPBITEN;
 				st->control |= AD9834_MODE;
 			} else if (st->control & AD9834_OPBITEN) {
-				ret = -EINVAL;	/* AD9843 reserved mode */
+				ret = -EINVAL;	/* AD9834 reserved mode */
 			} else {
 				st->control |= AD9834_MODE;
 			}