Update licensing and switch back to GPLv3 😅

include/cdecl16.inc

@@ -1,22 +1,18 @@
-; Copyright (c) 2024 Elaina Claus
-;
-; Permission is hereby granted, free of charge, to any person obtaining a copy
-; of this software and associated documentation files (the "Software"), to deal
-; in the Software without restriction, including without limitation the rights
-; to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-; copies of the Software, and to permit persons to whom the Software is
-; furnished to do so, subject to the following conditions:
-;
-; The above copyright notice and this permission notice shall be included in all
-; copies or substantial portions of the Software.
-;
-; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-; IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-; FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-; AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-; LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-; OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-; SOFTWARE.
+; Copyright (C) 2025 Elaina Claus
+; 
+;     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 3 of the License, or
+;     (at your option) any later version.
+; 
+;     This program 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.
+; 
+;     You should have received a copy of the GNU General Public License
+;     along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
 %ifnmacro __CDECL16_ENTRY
 %macro __CDECL16_ENTRY 0
     push bp