Fix uvm_sequencer wrong reference type

[wsnyder]

Towards UVM elaboration #1538 fix class parameterization of the following:

function uvm_sequencer::new (string name, uvm_component parent=null);
  super.new(name, parent);
  //vvv %Error: t/t_uvm_pkg_todo.vh:19869:21: Function Argument expects a CLASSREFDTYPE 'uvm_sequencer__Tz97_TBz97', got CLASSREFDTYPE 'uvm_sequencer__Tz97'
  seq_item_export = new ("seq_item_export", this);
endfunction

[donlon]

V3Param doesn't generate correct new name for some parameterized classes. I think I could have a try to fix it...