Extend mod_status output to include SSL session cache status

Extend mod_status output to include SSL session cache status
information:

* modules/ssl/mod_ssl.c (ssl_hook_pre_config): Call
ssl_scache_status_register.

* modules/ssl/ssl_scache.c (ssl_scache_status): Removed function.
(ssl_ext_status_hook): Renamed from ssl_ext_ms_display: switch to
2.1's mod_status "status_hook" API.
(ssl_scache_status_register): Register optional hook.

* modules/ssl/ssl_scache_dbm.c (ssl_scache_dbm_status): Adjust to use
new API.

* modules/ssl/ssl_scache_shmcb.c (ssl_scache_shmcb_status): Adjust
to use new API.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@101889 13f79535-47bb-0310-9956-ffa450edef68