unbound: Fix "register DHCP leases in DNS" config option
unbound: Fix "register DHCP leases in DNS" config option

The option to register DHCP leases within unbound DNS was configurable via
DNS Resolver GUI, but the setting was ignored. DHCP leases were always applied.

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