Bug 13399

Failure is observed in automated testing on Autobuilder.

https://autobuilder.yocto.io/pub/releases/yocto-2.8_M1.rc2/testresults/testresult-report.txt 

https://autobuilder.yocto.io/pub/releases/yocto-2.8_M1.rc2/testresults/qemux86/testresults.json

Error observed below:
"runqemu.RunqemuTests.test_boot_machine_slirp": {
                "log": "testtools.testresult.real._StringException: Traceback (most recent call last):\n  File \"/home/pokybuild/yocto-worker/qemux86/build/meta/lib/oeqa/selftest/cases/runqemu.py\", line 107, in test_boot_machine_slirp\n    with runqemu(self.recipe, ssh=False, launch_cmd=cmd) as qemu:\n  File \"/usr/lib64/python3.7/contextlib.py\", line 112, in __enter__\n    return next(self.gen)\n  File \"/home/pokybuild/yocto-worker/qemux86/build/meta/lib/oeqa/utils/commands.py\", line 339, in runqemu\n    qemu.start(params=qemuparams, ssh=ssh, runqemuparams=runqemuparams, launch_cmd=launch_cmd, discard_writes=discard_writes)\n  File \"/home/pokybuild/yocto-worker/qemux86/build/meta/lib/oeqa/targetcontrol.py\", line 164, in start\n    start = self.runner.launch(get_ip=ssh, launch_cmd=launch_cmd, qemuparams=params)\n  File \"/home/pokybuild/yocto-worker/qemux86/build/meta/lib/oeqa/utils/qemurunner.py\", line 207, in launch\n    while not self.is_alive() and time.time() < endtime:\n  File \"/home/pokybuild/yocto-worker/qemux86/build/meta/lib/oeqa/utils/qemurunner.py\", line 431, in is_alive\n    qemupid = int(qemu_pid)\nValueError: invalid literal for int() with base 10: ''\n\n",
                "status": "ERROR"
            },