Add Blackwell tensor RTL scaffolding

hw/rtl/mem/VX_tc_bus_if.sv

@@ -20,7 +20,10 @@ interface VX_tc_bus_if #(
 )();
 
     typedef struct packed {
+        logic                   rw;
+        logic [DATA_SIZE-1:0]   byteen;
         logic [ADDR_WIDTH-1:0] addr;
+        logic [DATA_SIZE*8-1:0] data;
         logic [TAG_WIDTH-1:0] tag;
     } req_data_t;