Fix include on Apache 2.4 when no matching files exist

systest on F19 caught this:

    Syntax error on line 97 of /etc/httpd/conf.d/05-foreman-ssl.conf: No matches for the wildcard '*.conf' in '/etc/httpd/conf.d/05-foreman-ssl.d', failing (use IncludeOptional if required)

http://httpd.apache.org/docs/2.4/mod/core.html#include