Merge r1827865 from trunk:

Use 'ap_log_rerror()' instead of 'ap_log_error()' consistently
Submitted by: jailletc36
Reviewed by: jailletc36, jorton, ylavic


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1828745 13f79535-47bb-0310-9956-ffa450edef68