api: fix license headers in MM API

The libmm-glib library, as well as the ModemManager headers installed as part of the D-Bus service API, have always been LGPLv2+ licensed, because we want users of the service to rely on them in their own programs, even if they are proprietary.

Some files had an incorrect GPLv2+ header instead of the LGPLv2+ and that was confusing. All public headers in the MM API have the correct license text now.

Signed-off-by: Aleksander Morgado aleksandermj@chromium.org

include/ModemManager-compat.h

 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
 /*
- * 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 of the License, or
- * (at your option) any later version.
+ * ModemManager Interface Specification
  *
- * This program is distributed in the hope that it will be useful,
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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:
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
  *
  * Copyright (C) 2017 Google, Inc.
  */