Type: man jpa-setup
You should in the resulting page, the following information (note that the valid choices are incorrect:
-j, --jpaVersion
JPA Version - [JPAFacet] (required) Valid choices: [ "org.jboss.forge.addon.javaee.jpa.JPAFacetImpl_2_1@1f" "org.jboss.forge.addon.javaee.jpa.JPAFacetImpl_2_0@1f" ]