DataSourceDefinition is registering capabilities for deployment tree resources

The same DataSourceDefinition class is used for registering the MRR for the subsystem=data-sources/(xa-)data-source=* resources and for their equivalents in the /deployment=* tree. In both cases the registerCapabilities() method is recording the datasource capability.

The deployment resources are not actually able to provide the capability[1], so it shouldn't be registered in that case. I believe the DataSourceDefinition.deployed field can be used to turn this off.

[1] Capabilities are management model concepts and can't be provided by services and runtime-only resources. The /deployment=/subsystem= resources are runtime-only.