transport: Move printing of reader number/name to generic code

Let's avoid copy+pasting print statements everywhere.  The instances
do already have a __str__ method for the purpose of printing their name in a
generic way.

Change-Id: I663a9ea69bf7e7aaa6502896b6a71ef692f8d844

pySim/transport/serial.py

@@ -29,14 +29,11 @@ from pySim.utils import h2b, b2h, Hexstr, ResTuple
 
 class SerialSimLink(LinkBase):
     """ pySim: Transport Link for serial (RS232) based readers included with simcard"""
+    name = 'Serial'
 
     def __init__(self, opts = argparse.Namespace(device='/dev/ttyUSB0', baudrate=9600), rst: str = '-rts',
                  debug: bool = False, **kwargs):
         super().__init__(**kwargs)
-        if os.environ.get('PYSIM_INTEGRATION_TEST') == "1":
-            print("Using serial reader interface")
-        else:
-            print("Using serial reader interface at port %s" % opts.device)
         if not os.path.exists(opts.device):
             raise ValueError("device file %s does not exist -- abort" % opts.device)
         self._sl = serial.Serial(