Downgrading squid3

[Joshua Root]

It's pretty garbled because of overlapping output from multiple make
jobs (append 'build.jobs=1' to the command to avoid this BTW), but it
looks like the failure is due to a compiler warning about a tautological
comparison, which is escalated to an error because -Werror is used.

The current squid3 portfile has --disable-strict-error-checking in
configure.args to prevent the use of -Werror.

(BTW, please don't send full logs to the list; most subscribers likely
don't want to see or download them. Host them somewhere, e.g. a pastebin
service, and send the URL to the list.)

- Josh