Remove still dangling HAVE_SNPRINTF stuff. Dean has removed the include/conf.h

hack, so this define is no longer useable thus there is no need for
documenting it any longer.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@80719 13f79535-47bb-0310-9956-ffa450edef68