merge from trunk:

rotatelogs: Improve error message for open failures.

PR: 39487
Submitted by: jorton
Reviewed by: trawick, jim, wrowe


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@486612 13f79535-47bb-0310-9956-ffa450edef68