Merge r953377,r953385,r953418 from trunk:

mod_proxy_http, mod_proxy_ajp, mod_reqtimeout:
Use APR_STATUS_IS_TIMEUP instead of direct compare
to APR_TIMEUP to be more safe on different platforms.

Submitted by: rjung, rpluem
Reviewed by: rjung, rpluem, wrowe


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@953616 13f79535-47bb-0310-9956-ffa450edef68