tests: reenable read of syslog on serial console

This now not only makes sense becuase we have live logging it also fixes
TODO pointed there, we just wait for file to appear (syslog-ng to
start).

tests/conftest.py

@@ -123,8 +123,7 @@ def fixture_client_board(board_serial, board_root_password, lan1_client):
     This is prefered over serial console as kernel logs are preferably printed there and that can break CLI machinery.
     """
     # Let's have syslog on serial console as well as kernel log
-    # TODO this fails as there is no /var/log/messages immediatelly after bootup for some reason
-    #board_serial.command('tail -f /var/log/messages')
+    board_serial.command('while ! [ -f /var/log/messages ]; do sleep 1; done && tail -f /var/log/messages')
     # Now spawn client container and connect
     nsfarm.cli.Shell(lan1_client.pexpect()).run('wait4network')
     pexp = lan1_client.pexpect(['ssh', '192.168.1.1'])
@@ -133,8 +132,8 @@ def fixture_client_board(board_serial, board_root_password, lan1_client):
     pexp.expect_exact("root@turris:")
     yield nsfarm.cli.Shell(pexp, flush=False)  # TODO drop this flush disable when it works
     # Kill tail -f on serial console
-    #board_serial.send('\x03')
-    #board_serial.prompt()
+    board_serial.send('\x03')
+    board_serial.prompt()
 
 
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