decode: handle FUNCTION_CLASS_INTERFACE requests like CONTROL_TRANSFER

The Novatel USB551L uses these to send data to the device, but the data
is QMUX.

decode/qmux.py

@@ -65,6 +65,8 @@ class Tlv:
             cmd = svc[1][self.cmdno]
         except KeyError:
             pass
+        except TypeError:
+            pass
         tlvlist = None
         if self.direction == TP_REQUEST:
             tlvlist = cmd[1]
@@ -184,6 +186,8 @@ def show(data, prefix, direction):
         scmd = qmi_cmd_to_string(cmdno, service)
     except KeyError:
         pass
+    except TypeError:
+        pass
     print prefix + "  Cmd:    0x%04x (%s)" % (cmdno, scmd)
 
     print prefix + "  Size:   0x%04x" % size