Fix the null statement warnings in a manner that avoids hassles should

anyone start checking the return values.  Also fix create_mutex() in the
non-multithreaded case in preparation for someone checking the return
values in the multithreaded case.  HINT HINT.  I would have started checking
the values except I'm not totally sure what to do to report errors.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@78317 13f79535-47bb-0310-9956-ffa450edef68