filesystem: SDL_EnumerateDirectory should return -1 or 0.

The callback requesting a non-error stop should not return a special value.

include/SDL3/SDL_filesystem.h

@@ -265,7 +265,10 @@ typedef struct SDL_PathInfo
  */
 extern DECLSPEC int SDLCALL SDL_CreateDirectory(const char *path);
 
-/* Callback for directory enumeration. Return 1 to keep enumerating, 0 to stop enumerating (no error), -1 to stop enumerating and report an error. `dirname` is the directory being enumerated, `fname` is the enumerated entry. */
+/* Callback for directory enumeration. Return 1 to keep enumerating,
+   0 to stop enumerating (no error), -1 to stop enumerating and
+   report an error. `dirname` is the directory being enumerated,
+   `fname` is the enumerated entry. */
 typedef int (SDLCALL *SDL_EnumerateDirectoryCallback)(void *userdata, const char *dirname, const char *fname);
 
 /**