JDBC driver's xa-datasource-class vs. driver-xa-datasource-class-name in the datasources subsystem

The jdbc-driver=* management resources in the datasources subsystem has two attributes, xa-datasource-class and driver-xa-datasource-class-name, whose difference isn't clear. Per wildfly-dev discussion [1], the xa-datasource-class has actually no meaning. IMHO, at the very least, it should be marked as deprecated with an explanation of something like "ignored" or so. Ultimately, removal is IMHO a good idea.

I'd also like to note that this actually caused a bug in WildFly Swarm: SWARM-1215

[1] http://lists.jboss.org/pipermail/wildfly-dev/2017-May/005913.html