More non C89 compliant comments

src/video/windows/SDL_windowsevents.c

@@ -533,7 +533,7 @@ WIN_WindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
                 break;
             }
         }
-        // no break
+        /* no break */
     case WM_CHAR:
         {
             char text[5];

src/video/windows/SDL_windowswindow.c

@@ -157,7 +157,7 @@ SetupWindowData(_THIS, SDL_Window * window, HWND hwnd, SDL_bool created)
             int w = rect.right;
             int h = rect.bottom;
             if ((window->w && window->w != w) || (window->h && window->h != h)) {
-                // We tried to create a window larger than the desktop and Windows didn't allow it.  Override!
+                /* We tried to create a window larger than the desktop and Windows didn't allow it.  Override! */
                 WIN_SetWindowPositionInternal(_this, window, SWP_NOCOPYBITS | SWP_NOZORDER | SWP_NOACTIVATE);
             } else {
                 window->w = w;