Downgrade error log messages which accompany a 404 request status from loglevel

error to info.

List thread at
http://mail-archives.apache.org/mod_mbox/httpd-dev/201110.mbox/%3Calpine.DEB.2.00.1110041948280.664@eru.sfritsch.de%3E

PR: 35768


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1180328 13f79535-47bb-0310-9956-ffa450edef68