Disable EUI during compilation

Logs on Mountain Lion fill with the following message when EUI is enabled (which it is by default).

---[ BEGIN ERROR ]---
ERROR: ARP / MAC / EUI-* operations not supported on this operating system.
---[ END ERROR ]---

See the following for more information.
http://www.squid-cache.org/mail-archive/squid-users/201304/0078.html
http://www.mentby.com/Group/squid-users/erro-arp-mac-eui-operations-not-supported-on-this-operating-system.html