enumerator: Fall back to lstat() if stat() fails when enumerating dirs/files

This happens e.g. if the path is for an invalid symlink.

src/libstrongswan/utils/compat/windows.h

@@ -222,6 +222,11 @@ static inline int setenv(const char *name, const char *value, int overwrite)
 	return 0;
 }
 
+/**
+ * stat(2) behaves like lstat(2) for symbolic links on Windows
+ */
+#define lstat stat
+
 /**
  * Lazy binding, ignored on Windows
  */