Correct initialization of variable `allowed_globals' in http_main.c

Submitted by: Justin Bradford <justin@ukans.edu>
Reviewed by: Ralf S. Engelschall
PR: 2400


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@81529 13f79535-47bb-0310-9956-ffa450edef68