dm raid: delete the redundant word 'that' in comment

Signed-off-by: Jilin Yuan <yuanjilin@cdjrlc.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index c640be4..e448fd4 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -2529,7 +2529,7 @@ static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
 		 * of the "sync" directive.
 		 *
 		 * With reshaping capability added, we must ensure that
-		 * that the "sync" directive is disallowed during the reshape.
+		 * the "sync" directive is disallowed during the reshape.
 		 */
 		if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
 			continue;