md/raid5: Use is_power_of_2() in raid5_reconfig()/raid6_reconfig().

Signed-off-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index eaa2d3e..72e8a32 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -5167,8 +5167,7 @@
 	if (new_layout >= 0 && !algorithm_valid_raid5(new_layout))
 		return -EINVAL;
 	if (new_chunk > 0) {
-		if (new_chunk & (new_chunk-1))
-			/* not a power of 2 */
+		if (!is_power_of_2(new_chunk))
 			return -EINVAL;
 		if (new_chunk < PAGE_SIZE)
 			return -EINVAL;
@@ -5206,8 +5205,7 @@
 	if (new_layout >= 0 && !algorithm_valid_raid6(new_layout))
 		return -EINVAL;
 	if (new_chunk > 0) {
-		if (new_chunk & (new_chunk-1))
-			/* not a power of 2 */
+		if (!is_power_of_2(new_chunk))
 			return -EINVAL;
 		if (new_chunk < PAGE_SIZE)
 			return -EINVAL;