Fix builed error after commit 0e45b824e34 due to -Wunused-variable

src/render/SDL_render.c

@@ -2699,8 +2699,6 @@ bool SDL_GetRenderLogicalPresentationRect(SDL_Renderer *renderer, SDL_FRect *rec
 
     if (rect) {
         if (renderer->logical_presentation_mode == SDL_LOGICAL_PRESENTATION_DISABLED) {
-            int output_w = 0, output_h = 0;
-
             rect->x = 0.0f;
             rect->y = 0.0f;
             rect->w = (float)renderer->output_pixel_w;