SDL_events.c: override of SDL_PRIs64 for mingw is no longer needed

(cherry picked from commit 65d911aff094e404f543b28fc55141a88e3bd277)

src/events/SDL_events.c

@@ -34,13 +34,6 @@
 #include "../video/SDL_sysvideo.h"
 #include "SDL_syswm.h"
 
-#undef SDL_PRIs64
-#if (defined(__WIN32__) || defined(__GDK__)) && !defined(__CYGWIN__)
-#define SDL_PRIs64 "I64d"
-#else
-#define SDL_PRIs64 "lld"
-#endif
-
 /* An arbitrary limit so we don't have unbounded growth */
 #define SDL_MAX_QUEUED_EVENTS 65535