oeqa/utils/qemurunner: Avoid tracebacks on closed files
Reorder the shutdown/teardown to avoid:
File "/home/pokybuild/yocto-worker/oe-selftest-ubuntu/build/meta/lib/oeqa/utils/qemurunner.py", line 224, in launch
op = self.getOutput(output)
File "/home/pokybuild/yocto-worker/oe-selftest-ubuntu/build/meta/lib/oeqa/utils/qemurunner.py", line 90, in getOutput
fl = fcntl.fcntl(o, fcntl.F_GETFL)
ValueError: I/O operation on closed file
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
