mpm_winnt: Remove an obsolete comment in child.c explaining why the

declarations of the structures and functions to access the completion
contexts reside in a header file.

This no longer holds, as all the necessary functions and structures are
located in the single .c file (child.c).


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1801749 13f79535-47bb-0310-9956-ffa450edef68