Fix a typo in mod_deflate's m4 config section.

Submitted by:	albert chin (china@thewrittenword.com)
Reviewed by:	Justin Erenkrantz


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@92743 13f79535-47bb-0310-9956-ffa450edef68