* Only log a 408 if it is no keepalive timeout.

PR: 39785
Submitted by: Mark Montague <markmont umich.edu>, rpluem
Reviewed by: rpluem


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@919323 13f79535-47bb-0310-9956-ffa450edef68