Update mdev/dmcache.mdev

Add license identifier and description.

mdev/dmcache.mdev

@@ -1,25 +1,30 @@
-#!/bin/sh
-
-uuid_file="/etc/dmcache-uuids"
-
-# Check if the file exists
-if [ ! -f "$uuid_file" ]; then
-    echo "Error: File '$uuid_file' not found."
-    exit 1
-fi
-
-# Loop through each UUID in the file and remove the corresponding symlink
-while IFS= read -r uuid; do
-
-	if [ -z "$uuid" ] || [ "${uuid:0:1}" = "#" ]; then
-		continue
-	fi
-
-    symlink="/dev/disk/by-uuid/$uuid"
-
-    # Check if the symlink exists
-    if [ -L "$symlink" ]; then
-        echo "Removing symlink: $symlink"
-        rm "$symlink"
-    fi
-done < "$uuid_file"
+#!/bin/sh
+
+# mdev script to mask dm-cache origin device's FS UUID
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+# Copyright 2023 Forza <forza@tnonline.net>
+
+uuid_file="/etc/dmcache-uuids"
+
+# Check if the file exists
+if [ ! -f "$uuid_file" ]; then
+    echo "Error: File '$uuid_file' not found."
+    exit 1
+fi
+
+# Loop through each UUID in the file and remove the corresponding symlink
+while IFS= read -r uuid; do
+
+	if [ -z "$uuid" ] || [ "${uuid:0:1}" = "#" ]; then
+		continue
+	fi
+
+    symlink="/dev/disk/by-uuid/$uuid"
+
+    # Check if the symlink exists
+    if [ -L "$symlink" ]; then
+        echo "Removing symlink: $symlink"
+        rm "$symlink"
+    fi
+done < "$uuid_file"