interfaces: push dhclient and dhcp6c to system log
interfaces: push dhclient and dhcp6c to system log

Easier to see what's going on, both trigger most system reconfigure
events anyway.

PR: https://github.com/opnsense/core/issues/3197
Discussed with: @adschellevis

opnsense/core,opnsense/core,opnsense/core,opnsense/core,opnsense/core,opnsense/core