SCP file to remote device.

        Return (status, msg)
        status = boolean
        msg = details on what happened

def _scp_file(self, source_file, dest_file, file_system):
        """
        SCP file to remote device.

        Return (status, msg)
        status = boolean
        msg = details on what happened
        """
        return self._xfer_file(
            source_file=source_file,
            dest_file=dest_file,
            file_system=file_system,
            TransferClass=FileTransfer,
        )