move-do: copy from pre-bitboard version

src/move-do.h

@@ -0,0 +1,20 @@
+/* move-do.h - move do/undo.
+ *
+ * Copyright (C) 2021 Bruno Raoult ("br")
+ * Licensed under the GNU General Public License v3.0 or later.
+ * Some rights reserved. See COPYING.
+ *
+ * You should have received a copy of the GNU General Public License along with this
+ * program. If not, see <https://www.gnu.org/licenses/gpl-3.0-standalone.html>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later <https://spdx.org/licenses/GPL-3.0-or-later.html>
+ *
+ */
+
+#ifndef MOVE_DO_H
+#define MOVE_DO_H
+
+//extern pos_t *move_do(pos_t *pos, move_t *move);
+//extern void move_undo(pos_t *pos, move_t *move);
+
+#endif  /* MOVE_DO_H */