Resources: Add SDL to thirdparty.html

data/resources/thirdparty.html

@@ -747,6 +747,26 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE.
 </h3>
 
+<h3>SDL - <a href="https://github.com/libsdl-org/SDL">https://github.com/libsdl-org/SDL</a></h3>
+<pre>Simple DirectMedia Layer
+  Copyright (C) 1997-2024 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.</pre>
+
 <h3>simpleini - <a href="https://github.com/brofield/simpleini">https://github.com/brofield/simpleini</a></h3>
 <pre>
 The MIT License (MIT)