Fixed typo (thanks @Iniquitatis!)

src/video/x11/SDL_x11window.c

@@ -998,7 +998,7 @@ void X11_SetWindowSize(_THIS, SDL_Window *window)
 
         if (SDL_GetTicks() >= timeout) {
             /* Timeout occurred and window size didn't change
-             * wwindow manager likely denied the resize. */
+             * window manager likely denied the resize. */
             window->w = orig_w;
             window->h = orig_h;
             break;