host_communication/card_emu: adapt to nwe req_ctx / queuing paradignm

firmware/src_simtrace/main.c

@@ -140,7 +140,6 @@ extern int main( void )
             last_simtrace_config = simtrace_config;
         } else {
             config_func_ptrs[simtrace_config].run();
-	    usb_to_host();
         }
     }
 }