Log Message:
Import dhcpcd-7.0.0 with the following changes:
  *  dhcp: when unicasting on L3, unicast on L2 as well
  *  dhcp: when rebooting, don't set cidaddr
  *  dhcp6: don't listen on IPv6 addresses when not using DHCPv6
  *  dhcp: only set probe state when probing (fixes REBOOT reason)
  *  linux: use IFA_F_NOPREFIXROUTE for IPv4 addresses
  *  ipv6: disable kernel RA if interface is active
  *  hooks: set protocol to link for link layer events