Fix double dbg definition if DEBUG_INCLUDE_CMD is set under OS2.

PR: 2917
Obtained from:
Submitted by:   Brian Carr <brian_carr@usa.net>
Reviewed by:


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@82004 13f79535-47bb-0310-9956-ffa450edef68