fix typo

  This file gives a brief overview of the major changes between each OpenSSL

  release. For more details please read the CHANGES file.

  Major changes between OpenSSL 0.9.7c and OpenSSL 0.9.8d:

  Major changes between OpenSSL 0.9.8c and OpenSSL 0.9.8d:

      o Introduce limits to prevent malicious key DoS  (CVE-2006-2940)

      o Fix security issues (CVE-2006-2937, CVE-2006-3737, CVE-2006-4343)