Merge r599651, r608508, r611376 from trunk:

Get rid of some compiler warnings.

* Silence a compiler warning by using the correct format.

* Hex pids are bogus anyway and on environments with APR_PID_T_FMT d this
  breaks and print x.

Submitted by: rpluem
Reviewed by: rpluem, covener, trawick


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@614661 13f79535-47bb-0310-9956-ffa450edef68