dhclient - Drop medium/alias useless utilization.

dhclient - Drop medium/alias useless utilization.

- Dump some useless calls to dhclient-script. i.e. MEDIUM, PREINIT,
  ARPSEND, ARPCHECK. Drop support for 'media', 'medium' and 'alias'
  specifications in dhclient.conf.
- Old leases still parse but these options now have no effect.
- Be more polite and decline all offers we don't accept.
- Fix a IMSG length check.
- Many expressions of support at various bars.

Taken-from: OpenBSD