Log Message:
Import dhcpcd-6.10.0 with the following changes:
  *  --noption requires an argument
  *  optimise the ARP BPF filter, thanks to Nate Karstens
  *  send gratuitous ARP each time we apply our IP address
  *  fix truncation of hostnames based on the short hostname option
  *  improve routing and address management by always loading all
     interfaces, routes and addresses even for interfaces we are
     not directly working on
  *  timezone, lookup-hostname, wpa_supplicant and YP hooks are no
     longer installed by default but are installed to an example
     directory
  *  fix compile on kFreeBSD
     thanks to Christoph Egger for providing a temporary build host
  *  improve error logging of packet parsing
  *  fix ignoring routing messages generated by dhcpcd just before
     forking
  *  fix handling of rapid commit messages (allow ACK after DISCOVER)
  *  add PROBE state so we can easily reject DHCP messages received
     during the ARP probe phase
  *  fix CVE-2016-1503
  *  fix CVE-2016-1504