Provide error code in log message for timeout_server

This isn't always called on a timeout

Change-Id: I1600e77503f17da7261a1cb1422db97638298736
Reviewed-on: http://review.couchbase.org/34953
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Brett Lawson <brett19@gmail.com>