- Fix a bug to miscalculate when compute a checksum in IPv4 -> IPv4   translation. - Remove natpt_recalculateTCP4Checksum() and related #include.   This function became useless by modification mentioned above.
- Fix a bug to miscalculate when compute a checksum in IPv4 -> IPv4
  translation.
- Remove natpt_recalculateTCP4Checksum() and related #include.
  This function became useless by modification mentioned above.

MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame