Standardize Levitte's dual-license

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3689)
diff --git a/crypto/LPdir_win32.c b/crypto/LPdir_win32.c
index 59ed485..9e6ca6d 100644
--- a/crypto/LPdir_win32.c
+++ b/crypto/LPdir_win32.c
@@ -8,6 +8,9 @@
  */
 
 /*
+ * This file is dual-licensed and is also avialable under the following
+ * terms:
+ *
  * Copyright (c) 2004, Richard Levitte <richard@levitte.org>
  * All rights reserved.
  *