Rename m4_startup.* to more appropriate core_control.*

Now that there is M0- and M4-related code.

firmware/application/core_control.hpp

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
+ *
+ * This file is part of PortaPack.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#ifndef __CORE_CONTROL_H__
+#define __CORE_CONTROL_H__
+
+#include <cstddef>
+
+#include "memory_map.hpp"
+#include "spi_image.hpp"
+
+void m4_init(const portapack::spi_flash::region_t from, const portapack::memory::region_t to);
+void m4_request_shutdown();
+
+void m0_halt();
+
+#endif/*__CORE_CONTROL_H__*/