gles2gsg: fix compilation error with OpenGL ES 2

panda/src/glstuff/glGraphicsStateGuardian_src.cxx

@@ -7585,7 +7585,7 @@ make_shadow_buffer(LightLensNode *light, Texture *tex, GraphicsOutput *host) {
     flags |= GraphicsPipe::BF_size_square;
   }
 
-  CLP(GraphicsBuffer) *sbuffer = new GLGraphicsBuffer(get_engine(), get_pipe(), light->get_name(), fbp, props, flags, this, host);
+  CLP(GraphicsBuffer) *sbuffer = new CLP(GraphicsBuffer)(get_engine(), get_pipe(), light->get_name(), fbp, props, flags, this, host);
   sbuffer->add_render_texture(tex, GraphicsOutput::RTM_bind_or_copy, GraphicsOutput::RTP_depth);
   get_engine()->add_window(sbuffer, light->get_shadow_buffer_sort());
   return sbuffer;