Update title and description for jboss-eap5-xml-16000 rule

Please update the title to:
“JBoss security configuration descriptor (login-config.xml)”

And the description to:
Before JBoss EAP 6, authentication security domains and login modules could be configured in a “login-config.xml” file.
JBoss EAP 6+ does not support the “login-config.xml” descriptor. Security is now configured inside the server configuration. Please refer to the corresponding server security guide.

(The link can remain as-is.)