Add copyright information

src/kconf_update/kalarm-1.2.1-general.pl

 #!/usr/bin/perl -w
 # Convert KAlarm pre-1.2.1 General section settings.
 
+# SPDX-FileCopyrightText: 2010 David Jarvie <djarvie@kde.org>
 # SPDX-License-Identifier: GPL-2.0-or-later
 
 use strict;

src/kconf_update/kalarm-1.9.5-defaults.pl

 #!/usr/bin/perl -w
 # Convert pre-1.9.5 Defaults section settings.
 
+# SPDX-FileCopyrightText: 2010 David Jarvie <djarvie@kde.org>
 # SPDX-License-Identifier: GPL-2.0-or-later
 
 use strict;

src/kconf_update/kalarm-2.0.2-general.pl

 #!/usr/bin/perl -w
 # Convert pre-2.0.2 General section settings.
 
+# SPDX-FileCopyrightText: 2008 David Jarvie <djarvie@kde.org>
 # SPDX-License-Identifier: GPL-2.0-or-later
 
 use strict;

src/kconf_update/kalarm-2.1.5-general.pl

 #!/usr/bin/perl -w
 # Convert pre-2.1.5 General section settings.
 
+# SPDX-FileCopyrightText: 2009 David Jarvie <djarvie@kde.org>
 # SPDX-License-Identifier: GPL-2.0-or-later
 
 use strict;