Fix a problem with the display of empty variables ("SetEnv foo") in

mod_include.
PR:               24734
Submitted by:	  Markus Julen <mj zermatt.net>
Reviewed by:	  trawick, nd, striker


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@101979 13f79535-47bb-0310-9956-ffa450edef68