Add GPL-3.0-or-later SPDX identifier to all scripts

Add the SPDX license identifier GPL-3.0-or-later to the header of all
scripts without a specific license and upgrading those that are stated
as GPL-2.0 to become GPL-3.0-or-later.

1 files changed, 2 insertions, 1 deletions

diff --git a/lib/valid-tags.sh b/lib/valid-tags.sh
index 3cfe046..d628fd1 100644
--- a/lib/valid-tags.sh
+++ b/lib/valid-tags.sh
@@ -1,5 +1,6 @@
 #!/hint/bash
-# License: Unspecified
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
 :
 
 # shellcheck disable=2034