doc: libvlc: add 's' shortcut to stop playback

doc/libvlc/win_player.c

@@ -85,6 +85,10 @@ static LRESULT CALLBACK WindowProc(HWND hWnd, UINT message, WPARAM wParam, LPARA
                         AspectRatio = NULL;
                     libvlc_video_set_aspect_ratio( ctx->p_mediaplayer, AspectRatio );
                 }
+                if (key == 's')
+                {
+                    libvlc_media_player_stop( ctx->p_mediaplayer );
+                }
                 break;
             }
         default: break;