virttest.qemu_virtio_port: Allow to reload loss idx from outside the thread

Usually the index of lost characters is reloaded while reconnection.
This patch creates a function, which can be called from outside of this
thread in case we want to reload this index elswhere. Additionally booth
(debug and normal) threads use the same code now.
Signed-off-by: NLukáš Doktor <ldoktor@redhat.com>

qemu/tests/virtio_console.py

@@ -988,6 +988,7 @@ def run_virtio_console(test, params, env):
                                      'test_time', test_time)
                     else:
                         break
+                threads[1].reload_loss_idx()
                 if count == threads[1].idx or not threads[1].isAlive():
                     if not threads[1].isAlive():
                         logging.error('RecvCheck thread stopped unexpectedly.')