inotify: Trivially add SPDX-License-Identifier to inotify files

The license and copyright are already stated in human-readable form in
these files, so this should be uncontroversial.

Signed-off-by: Philip Withnall <pwithnall@gnome.org>

Helps: #1415

gio/inotify/ginotifyfilemonitor.c

@@ -3,6 +3,8 @@
  * Copyright (C) 2006-2007 Red Hat, Inc.
  * Copyright (C) 2007 Sebastian Dröge.
  *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
  * 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

gio/inotify/ginotifyfilemonitor.h

@@ -3,6 +3,8 @@
  * Copyright (C) 2006-2007 Red Hat, Inc.
  * Copyright (C) 2007 Sebastian Dröge.
  *
+ * SPDX-License-Identifier: LGPL-2.1-or-later
+ *
  * 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

gio/inotify/inotify-helper.c

@@ -4,6 +4,8 @@
 
    Copyright (C) 2007 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-helper.h

@@ -2,6 +2,8 @@
 
    Copyright (C) 2007 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-kernel.c

@@ -2,6 +2,8 @@
    Copyright (C) 2005 John McCutchan
    Copyright © 2015 Canonical Limited
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-kernel.h

@@ -1,6 +1,8 @@
 /*
    Copyright (C) 2005 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-missing.c

@@ -4,6 +4,8 @@
 
    Copyright (C) 2005 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-missing.h

@@ -2,6 +2,8 @@
 
    Copyright (C) 2006 John McCutchan <john@johnmccutchan.com>
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-path.c

@@ -5,6 +5,8 @@
    Copyright (C) 2006 John McCutchan
    Copyright (C) 2009 Codethink Limited
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-path.h

@@ -1,6 +1,8 @@
 /*
    Copyright (C) 2005 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-sub.c

@@ -4,6 +4,8 @@
 
    Copyright (C) 2006 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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

gio/inotify/inotify-sub.h

@@ -2,6 +2,8 @@
 
    Copyright (C) 2006 John McCutchan
 
+   SPDX-License-Identifier: LGPL-2.1-or-later
+
    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