Fix piped logs in 2.0. This basically:

1) cleans up an annoying type that was getting in my way while I was
   trying to fix things.
2) Makes some of the allocations pcalloc instead of palloc
3) The arg array passed to create_process is a const *char *, not
   const *char [].
PR:     6642


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@86640 13f79535-47bb-0310-9956-ffa450edef68