README-migration.md: fix SDL_WINDOWEVENT_CLOSE renamed name.

SDL_EVENT_WINDOW_CLOSE_REQUESTED, not SDL_EVENT_WINDOW_CLOSE.

docs/README-migration.md

@@ -529,7 +529,7 @@ The following symbols have been renamed:
 * SDL_DISPLAYEVENT_DISCONNECTED => SDL_EVENT_DISPLAY_DISCONNECTED
 * SDL_DISPLAYEVENT_MOVED => SDL_EVENT_DISPLAY_MOVED
 * SDL_DISPLAYEVENT_ORIENTATION => SDL_EVENT_DISPLAY_ORIENTATION
-* SDL_WINDOWEVENT_CLOSE => SDL_EVENT_WINDOW_CLOSE
+* SDL_WINDOWEVENT_CLOSE => SDL_EVENT_WINDOW_CLOSE_REQUESTED
 * SDL_WINDOWEVENT_DISPLAY_CHANGED => SDL_EVENT_WINDOW_DISPLAY_CHANGED
 * SDL_WINDOWEVENT_ENTER => SDL_EVENT_WINDOW_ENTER
 * SDL_WINDOWEVENT_EXPOSED => SDL_EVENT_WINDOW_EXPOSED