Update SDL.zig, adapt Renderer.zig

lib/SDL.zig

@@ -1 +1 @@
-Subproject commit ab6ef00008f28f70a2dac89a949ad6685d8405ad
+Subproject commit 3843cb113f05bdd610449d082341f3e6a9769878

src/Renderer.zig

@@ -27,7 +27,7 @@ pub fn init() !Self {
         .{ .centered = {} },
         1280,
         720,
-        .{ .opengl = true, .shown = true }
+        .{ .context = .opengl, .vis = .shown }
     );
 
     const ctx = try sdl.gl.createContext(window);