See
<subsystem xmlns="urn:jboss:domain:ee:2.0">
and the element
<default-bindings>
Then point that to your datasource, and it will be exposed in java:comp
under the EE 7 name.
Not really related but that element is a mess. We should change it to use
elements rather than attributes so you do not end up with such a long line
when standalone.xml is re-written.
Stuart