MFC r264124:
  Remove dead code.

MFC r264125:
  Remove unused variable.

MFC r264126:
  The check for local address spoofing lacks ifaddr locking.
  Remove these loops and use in_localip() and in6_localip()
  functions instead.

MFC r264520:
  Remove _IP_VHL* macros and related ifdefs.
MFC: r264482

Re-indent break statement.
MFC: r264422, r264471

Set buf to NULL only when we don't allocate memory,
and free buf unconditionally.

Found with:	Coverity Prevent(tm)
Requested by:	kib (r264471)