`build_config_windows`: fix `HAVE_VSSCANF` defined regardless of MSVC version.

[sdl-ci-filter msvc-*]

include/build_config/SDL_build_config_windows.h

@@ -156,7 +156,6 @@ typedef unsigned int uintptr_t;
 #define HAVE_STRCMP 1
 #define HAVE_STRNCMP 1
 #define HAVE_STRPBRK 1
-#define HAVE_VSSCANF 1
 #define HAVE_VSNPRINTF 1
 #define HAVE_ACOS 1
 #define HAVE_ASIN 1