policycoreutils/sctp_test: Fix a few minor issues
    
    - userapp_t didn't have permission to write into temporary file which
    caused failure of the test even when sctp_test worked properly
    - Fix context of sctp_test during clean-up
    - Add listing of the new portcons to check they have been properly added
    
    Fixes: https://src.fedoraproject.org/tests/selinux/issue/21