remote/exporter: always set tcp for ser2net

Always indicate that the network connection should use tcp. This was not
mandatory for versions before 4.6.0, but is for versions afterwards.
This should not impact the behavior for earlier versions, since all
versions since the introduction of YAML configurations in 4.2.0 support
this parameter.

Fixes #1416

Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de>

Author: Emantor

labgrid/remote/exporter.py

@@ -248,7 +248,7 @@ def _start(self, start_params):
                 "-d",
                 "-n",
                 "-Y",
-                f"connection: &con01#  accepter: telnet(rfc2217,mode=server),{self.port}",
+                f"connection: &con01#  accepter: telnet(rfc2217,mode=server),tcp,{self.port}",
                 "-Y",
                 f'  connector: serialdev(nouucplock=true),{start_params["path"]},{self.local.speed}n81,local',  # pylint: disable=line-too-long
                 "-Y",