wrcore_v2: adding dummy src and snk to fabric_pkg

modules/fabric/wr_fabric_pkg.vhd

@@ -59,7 +59,11 @@ package wr_fabric_pkg is
   function f_marshall_wrf_status (stat  : t_wrf_status_reg) return std_logic_vector;
   function f_unmarshall_wrf_status(stat : std_logic_vector) return t_wrf_status_reg;
 
-  
+  constant c_dummy_src_in : t_wrf_source_in :=
+    ('0', '0', '0', '0');
+  constant c_dummy_snk_in : t_wrf_sink_in :=
+    ((others=>'X'), (others=>'X'), '0', '0', 'X', (others=>'X'));
+
 end wr_fabric_pkg;
 
 package body wr_fabric_pkg is