simtrace.py: Find device without config change

The find_device() function was only called when the USB config was
altered. Now, it is called on every call of simtrace.py.

usb_application/simtrace.py

@@ -31,9 +31,9 @@ def main():
 
     args = parser.parse_args()
     print("args: ", args)
+    dev = find_dev()
 
     if args.conf is not None:
-        dev = find_dev()
         dev.set_configuration(args.conf)
         # Give pcsclite time to find the device
         time.sleep(1)