git-add -u: do not barf on type changes

Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin-add.c

@@ -98,6 +98,7 @@ static void update_callback(struct diff_queue_struct *q,
 			die("unexpacted diff status %c", p->status);
 		case DIFF_STATUS_UNMERGED:
 		case DIFF_STATUS_MODIFIED:
+		case DIFF_STATUS_TYPE_CHANGED:
 			add_file_to_cache(path, verbose);
 			break;
 		case DIFF_STATUS_DELETED: