video: Correct the window position property documentation

Windows are only relative to the parent if the "tooltip" or "menu" property is set.

include/SDL3/SDL_video.h

@@ -1228,10 +1228,10 @@ extern SDL_DECLSPEC SDL_Window * SDLCALL SDL_CreatePopupWindow(SDL_Window *paren
  * - `SDL_PROP_WINDOW_CREATE_WIDTH_NUMBER`: the width of the window
  * - `SDL_PROP_WINDOW_CREATE_X_NUMBER`: the x position of the window, or
  *   `SDL_WINDOWPOS_CENTERED`, defaults to `SDL_WINDOWPOS_UNDEFINED`. This is
- *   relative to the parent for windows with the "parent" property set.
+ *   relative to the parent for windows with the "tooltip" or "menu" property set.
  * - `SDL_PROP_WINDOW_CREATE_Y_NUMBER`: the y position of the window, or
  *   `SDL_WINDOWPOS_CENTERED`, defaults to `SDL_WINDOWPOS_UNDEFINED`. This is
- *   relative to the parent for windows with the "parent" property set.
+ *   relative to the parent for windows with the "tooltip" or "menu" property set.
  *
  * These are additional supported properties on macOS:
  *