apr_config.h is a private include file, and shouldn't be used by any

C files outside of APR.  ap_signal has been moved to apr.h, so this
include is no longer needed.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@84967 13f79535-47bb-0310-9956-ffa450edef68