exporter: add jtagd auto-detect-filter value to filter usb blaster devices

This filter of jtagd is only available for Blaster devices. However in
combination with the hwsf preload library it will work in mixed setups.

Author: sessl3r

labgrid/remote/exporter.py

@@ -396,6 +396,10 @@ def _start(self, start_params):
 
         cmd = f"{self.local.jtagd_cmd} --foreground --port {self.jtagd_port} --config {self.cfg_tempfile.name}"
 
+        # jtagd can filter Altera USB-Blaster devices by serial
+        if self.local.serial_short:
+            cmd += f" --auto-detect-filter {self.local.serial_short}"
+
         self.logger.info("starting jtagd for %s on port %s with command LD_PRELOAD+=%s HWSF_DEV=%s %s",
                          self.local.device.sys_name, self.jtagd_port, lib_path,
                          my_env['HWSF_DEV'], cmd)