iotests: Let 045 be run concurrently

Adding a telnet monitor for no real purpose on a fixed port is not so
great.  Just use a null monitor instead.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20190210145736.1486-10-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

scripts/qemu.py

@@ -144,10 +144,9 @@ class QEMUMachine(object):
         return False
 
     # This can be used to add an unused monitor instance.
-    def add_monitor_telnet(self, ip, port):
-        args = 'tcp:%s:%d,server,nowait,telnet' % (ip, port)
+    def add_monitor_null(self):
         self._args.append('-monitor')
-        self._args.append(args)
+        self._args.append('null')
 
     def add_fd(self, fd, fdset, opaque, opts=''):
         """

tests/qemu-iotests/045

@@ -132,7 +132,7 @@ class TestSCMFd(iotests.QMPTestCase):
         qemu_img('create', '-f', iotests.imgfmt, image0, '128K')
         # Add an unused monitor, to verify it works fine when two monitor
         # instances present
-        self.vm.add_monitor_telnet("0",4445)
+        self.vm.add_monitor_null()
         self.vm.launch()
 
     def tearDown(self):