default provider name, to allow consumers to use a default provider
if not configured otherwise.
* modules/cache/mod_socache_shmcb.c (register_hooks): Register shmcb
as the default provider.
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@724723 13f79535-47bb-0310-9956-ffa450edef68