Set enable_geoiplookup on cp1066 for geo_cookie

Nothing is relying on the GeoIP cookie yet, and there is no harm in having
Varnish set it on some requests and not on others. So rolling out to a single
node makes sense.

Change-Id: Ieacbbce2367830be37019b65d12ead05214f6ade
Merge "Set enable_geoiplookup on cp1066 for geo_cookie" into production