revision: append to list instead of insert and reverse

By using commit_list_insert(), we added new items to the top of the
list and, since this is not the order we want, reversed it afterwards.
Simplify this process by adding new items at the bottom instead,
getting rid of the reversal step.
Signed-off-by: NRene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

revision.c

@@ -2066,6 +2066,7 @@ int prepare_revision_walk(struct rev_info *revs)
 {
 	int nr = revs->pending.nr;
 	struct object_array_entry *e, *list;
+	struct commit_list **next = &revs->commits;
 
 	e = list = revs->pending.objects;
 	revs->pending.nr = 0;
@@ -2076,12 +2077,11 @@ int prepare_revision_walk(struct rev_info *revs)
 		if (commit) {
 			if (!(commit->object.flags & SEEN)) {
 				commit->object.flags |= SEEN;
-				commit_list_insert(commit, &revs->commits);
+				next = commit_list_append(commit, next);
 			}
 		}
 		e++;
 	}
-	commit_list_reverse(&revs->commits);
 	commit_list_sort_by_date(&revs->commits);
 	if (!revs->leak_pending)
 		free(list);